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<FONT color="green">001</FONT>    // Copyright 2006-2008 Waterken Inc. under the terms of the MIT X license<a name="line.1"></a>
<FONT color="green">002</FONT>    // found at http://www.opensource.org/licenses/mit-license.html<a name="line.2"></a>
<FONT color="green">003</FONT>    package org.ref_send.promise;<a name="line.3"></a>
<FONT color="green">004</FONT>    <a name="line.4"></a>
<FONT color="green">005</FONT>    import java.io.Serializable;<a name="line.5"></a>
<FONT color="green">006</FONT>    import java.lang.reflect.InvocationHandler;<a name="line.6"></a>
<FONT color="green">007</FONT>    import java.lang.reflect.Method;<a name="line.7"></a>
<FONT color="green">008</FONT>    import java.lang.reflect.Proxy;<a name="line.8"></a>
<FONT color="green">009</FONT>    import java.lang.reflect.Type;<a name="line.9"></a>
<FONT color="green">010</FONT>    import java.lang.reflect.TypeVariable;<a name="line.10"></a>
<FONT color="green">011</FONT>    <a name="line.11"></a>
<FONT color="green">012</FONT>    import org.joe_e.Equatable;<a name="line.12"></a>
<FONT color="green">013</FONT>    import org.joe_e.Immutable;<a name="line.13"></a>
<FONT color="green">014</FONT>    import org.joe_e.JoeE;<a name="line.14"></a>
<FONT color="green">015</FONT>    import org.joe_e.Selfless;<a name="line.15"></a>
<FONT color="green">016</FONT>    import org.joe_e.Struct;<a name="line.16"></a>
<FONT color="green">017</FONT>    import org.joe_e.Token;<a name="line.17"></a>
<FONT color="green">018</FONT>    import org.joe_e.array.ConstArray;<a name="line.18"></a>
<FONT color="green">019</FONT>    import org.joe_e.reflect.Proxies;<a name="line.19"></a>
<FONT color="green">020</FONT>    import org.joe_e.reflect.Reflection;<a name="line.20"></a>
<FONT color="green">021</FONT>    import org.ref_send.type.Typedef;<a name="line.21"></a>
<FONT color="green">022</FONT>    <a name="line.22"></a>
<FONT color="green">023</FONT>    /**<a name="line.23"></a>
<FONT color="green">024</FONT>     * The eventual operator.<a name="line.24"></a>
<FONT color="green">025</FONT>     * &lt;p&gt;This class decorates an event loop with methods implementing the core<a name="line.25"></a>
<FONT color="green">026</FONT>     * eventual control flow statements needed for defensive programming. The<a name="line.26"></a>
<FONT color="green">027</FONT>     * primary aim of these new control flow statements is preventing plan<a name="line.27"></a>
<FONT color="green">028</FONT>     * interference.&lt;/p&gt;<a name="line.28"></a>
<FONT color="green">029</FONT>     * &lt;p&gt;The implementation of a public method can be thought of as a plan in<a name="line.29"></a>
<FONT color="green">030</FONT>     * which an object makes a series of state changes based on a list of<a name="line.30"></a>
<FONT color="green">031</FONT>     * invocation arguments and the object's own current state. As part of<a name="line.31"></a>
<FONT color="green">032</FONT>     * executing this plan, the object may need to notify other objects of the<a name="line.32"></a>
<FONT color="green">033</FONT>     * changes in progress. These other objects may have their own plans to<a name="line.33"></a>
<FONT color="green">034</FONT>     * execute, based on this notification. Plan interference occurs when<a name="line.34"></a>
<FONT color="green">035</FONT>     * execution of these other plans interferes with execution of the original<a name="line.35"></a>
<FONT color="green">036</FONT>     * plan.&lt;/p&gt;<a name="line.36"></a>
<FONT color="green">037</FONT>     * &lt;h3&gt;Plan interference&lt;/h3&gt;<a name="line.37"></a>
<FONT color="green">038</FONT>     * &lt;p&gt;Interleaving plan execution is vulnerable to many kinds of interference.<a name="line.38"></a>
<FONT color="green">039</FONT>     * Each kind of interference is explained below, using the following example<a name="line.39"></a>
<FONT color="green">040</FONT>     * code:&lt;/p&gt;<a name="line.40"></a>
<FONT color="green">041</FONT>     * &lt;pre&gt;<a name="line.41"></a>
<FONT color="green">042</FONT>     * public final class<a name="line.42"></a>
<FONT color="green">043</FONT>     * Account {<a name="line.43"></a>
<FONT color="green">044</FONT>     *<a name="line.44"></a>
<FONT color="green">045</FONT>     *  private int balance;<a name="line.45"></a>
<FONT color="green">046</FONT>     *  private final ArrayList&amp;lt;Receiver&amp;lt;Integer&amp;gt;&amp;gt; observers;<a name="line.46"></a>
<FONT color="green">047</FONT>     *<a name="line.47"></a>
<FONT color="green">048</FONT>     *  Account(final int initial) {<a name="line.48"></a>
<FONT color="green">049</FONT>     *      balance = initial;<a name="line.49"></a>
<FONT color="green">050</FONT>     *      observers = new ArrayList&amp;lt;Receiver&amp;lt;Integer&amp;gt;&amp;gt;();<a name="line.50"></a>
<FONT color="green">051</FONT>     *  }<a name="line.51"></a>
<FONT color="green">052</FONT>     *<a name="line.52"></a>
<FONT color="green">053</FONT>     *  public void<a name="line.53"></a>
<FONT color="green">054</FONT>     *  observe(final Receiver&amp;lt;Integer&amp;gt; observer) {<a name="line.54"></a>
<FONT color="green">055</FONT>     *      if (null == observer) {<a name="line.55"></a>
<FONT color="green">056</FONT>     *          throw new NullPointerException();<a name="line.56"></a>
<FONT color="green">057</FONT>     *      }<a name="line.57"></a>
<FONT color="green">058</FONT>     *      observers.add(observer);<a name="line.58"></a>
<FONT color="green">059</FONT>     *  }<a name="line.59"></a>
<FONT color="green">060</FONT>     *<a name="line.60"></a>
<FONT color="green">061</FONT>     *  public int<a name="line.61"></a>
<FONT color="green">062</FONT>     *  getBalance() { return balance; }<a name="line.62"></a>
<FONT color="green">063</FONT>     *<a name="line.63"></a>
<FONT color="green">064</FONT>     *  public void<a name="line.64"></a>
<FONT color="green">065</FONT>     *  setBalance(final int newBalance) {<a name="line.65"></a>
<FONT color="green">066</FONT>     *      balance = newBalance;<a name="line.66"></a>
<FONT color="green">067</FONT>     *      for (final Receiver&amp;lt;Integer&amp;gt; observer : observers) {<a name="line.67"></a>
<FONT color="green">068</FONT>     *          observer.apply(newBalance);<a name="line.68"></a>
<FONT color="green">069</FONT>     *      }<a name="line.69"></a>
<FONT color="green">070</FONT>     *  }<a name="line.70"></a>
<FONT color="green">071</FONT>     * }<a name="line.71"></a>
<FONT color="green">072</FONT>     * &lt;/pre&gt;<a name="line.72"></a>
<FONT color="green">073</FONT>     * &lt;h4&gt;Unanticipated termination&lt;/h4&gt;<a name="line.73"></a>
<FONT color="green">074</FONT>     * &lt;p&gt;A method can terminate execution of its plan by throwing an exception.<a name="line.74"></a>
<FONT color="green">075</FONT>     * The plan may be terminated because it would violate one of the object's<a name="line.75"></a>
<FONT color="green">076</FONT>     * invariants or because the request is malformed. Unfortunately, throwing an<a name="line.76"></a>
<FONT color="green">077</FONT>     * exception may terminate not just the current plan, but also any other<a name="line.77"></a>
<FONT color="green">078</FONT>     * currently executing plans. For example, if one of the observers throws a<a name="line.78"></a>
<FONT color="green">079</FONT>     * {@link RuntimeException} from its {@code apply()} implementation, the<a name="line.79"></a>
<FONT color="green">080</FONT>     * remaining observers are not notified of the new account balance. These other<a name="line.80"></a>
<FONT color="green">081</FONT>     * observers may then continue operating using stale data about the account<a name="line.81"></a>
<FONT color="green">082</FONT>     * balance.&lt;/p&gt;<a name="line.82"></a>
<FONT color="green">083</FONT>     * &lt;h4&gt;Nested execution&lt;/h4&gt;<a name="line.83"></a>
<FONT color="green">084</FONT>     * &lt;p&gt;When a method implementation invokes a method on another object, it<a name="line.84"></a>
<FONT color="green">085</FONT>     * temporarily suspends progress on its own plan to let the called method<a name="line.85"></a>
<FONT color="green">086</FONT>     * execute its plan. When the called method returns, the calling method<a name="line.86"></a>
<FONT color="green">087</FONT>     * resumes its own plan where it left off. Unfortunately, the called method<a name="line.87"></a>
<FONT color="green">088</FONT>     * may have changed the application state in such a way that resuming the<a name="line.88"></a>
<FONT color="green">089</FONT>     * original plan no longer makes sense.  For example, if one of the observers<a name="line.89"></a>
<FONT color="green">090</FONT>     * invokes {@code setBalance()} in its {@code apply()} implementation,<a name="line.90"></a>
<FONT color="green">091</FONT>     * the remaining observers will first be notified of the balance after the<a name="line.91"></a>
<FONT color="green">092</FONT>     * update, and then be notified of the balance before the update. Again, these<a name="line.92"></a>
<FONT color="green">093</FONT>     * other observers may then continue operating using stale data about the<a name="line.93"></a>
<FONT color="green">094</FONT>     * account balance.&lt;/p&gt;<a name="line.94"></a>
<FONT color="green">095</FONT>     * &lt;h4&gt;Interrupted transition&lt;/h4&gt;<a name="line.95"></a>
<FONT color="green">096</FONT>     * &lt;p&gt;A called method may also initiate an unanticipated state transition in<a name="line.96"></a>
<FONT color="green">097</FONT>     * the calling object, while the current transition is still incomplete.  For<a name="line.97"></a>
<FONT color="green">098</FONT>     * example, in the default state, an {@code Account} is always ready to accept a<a name="line.98"></a>
<FONT color="green">099</FONT>     * new observer; however, this constraint is temporarily not met when the<a name="line.99"></a>
<FONT color="green">100</FONT>     * observer list is being iterated over. An observer could catch the<a name="line.100"></a>
<FONT color="green">101</FONT>     * {@code Account} in this transitional state by invoking {@code observe()} in<a name="line.101"></a>
<FONT color="green">102</FONT>     * its {@code apply()} implementation. As a result, a<a name="line.102"></a>
<FONT color="green">103</FONT>     * {@link java.util.ConcurrentModificationException} will be thrown when<a name="line.103"></a>
<FONT color="green">104</FONT>     * iteration over the observer list resumes. Again, this exception prevents<a name="line.104"></a>
<FONT color="green">105</FONT>     * notification of the remaining observers.&lt;/p&gt;<a name="line.105"></a>
<FONT color="green">106</FONT>     * &lt;h3&gt;Plan isolation&lt;/h3&gt;<a name="line.106"></a>
<FONT color="green">107</FONT>     * &lt;p&gt;The above plan interference problems are only possible because execution<a name="line.107"></a>
<FONT color="green">108</FONT>     * of one plan is interleaved with execution of another. Interleaving plan<a name="line.108"></a>
<FONT color="green">109</FONT>     * execution can be prevented by scheduling other plans for future execution,<a name="line.109"></a>
<FONT color="green">110</FONT>     * instead of allowing them to preempt execution of the current plan. This<a name="line.110"></a>
<FONT color="green">111</FONT>     * class provides control flow statements for scheduling future execution and<a name="line.111"></a>
<FONT color="green">112</FONT>     * receiving its results.&lt;/p&gt;<a name="line.112"></a>
<FONT color="green">113</FONT>     * &lt;h3&gt;Naming convention&lt;/h3&gt;<a name="line.113"></a>
<FONT color="green">114</FONT>     * &lt;p&gt;Since the control flow statements defined by this class schedule future<a name="line.114"></a>
<FONT color="green">115</FONT>     * execution, instead of immediate execution, they behave differently from the<a name="line.115"></a>
<FONT color="green">116</FONT>     * native control flow constructs in the Java language. To make the difference<a name="line.116"></a>
<FONT color="green">117</FONT>     * between eventual and immediate execution readily recognized by programmers<a name="line.117"></a>
<FONT color="green">118</FONT>     * when scanning code, some naming conventions are proposed. By convention, an<a name="line.118"></a>
<FONT color="green">119</FONT>     * instance of {@link Eventual} is held in a variable named "{@code _}".<a name="line.119"></a>
<FONT color="green">120</FONT>     * Additional ways of marking eventual operations with the '{@code _}' character<a name="line.120"></a>
<FONT color="green">121</FONT>     * are specified in the documentation for the methods defined by this class. All<a name="line.121"></a>
<FONT color="green">122</FONT>     * of these conventions make eventual control flow statements distinguishable by<a name="line.122"></a>
<FONT color="green">123</FONT>     * the character sequence "{@code _.}". Example uses are also shown in the<a name="line.123"></a>
<FONT color="green">124</FONT>     * method documentation for this class. The '{@code _}' character should only be<a name="line.124"></a>
<FONT color="green">125</FONT>     * used to identify eventual operations so that a programmer can readily<a name="line.125"></a>
<FONT color="green">126</FONT>     * identify operations that are expected to be eventual by looking for the<a name="line.126"></a>
<FONT color="green">127</FONT>     * &lt;b&gt;{@code _.}&lt;/b&gt; pseudo-operator.&lt;/p&gt;<a name="line.127"></a>
<FONT color="green">128</FONT>     * @see &lt;a href="http://www.erights.org/talks/thesis/"&gt;Section 13.1<a name="line.128"></a>
<FONT color="green">129</FONT>     *      "Sequential Interleaving Hazards" of "Robust Composition: Towards a<a name="line.129"></a>
<FONT color="green">130</FONT>     *      Unified Approach to Access Control and Concurrency Control"&lt;/a&gt;<a name="line.130"></a>
<FONT color="green">131</FONT>     */<a name="line.131"></a>
<FONT color="green">132</FONT>    public class<a name="line.132"></a>
<FONT color="green">133</FONT>    Eventual implements Selfless, Serializable {<a name="line.133"></a>
<FONT color="green">134</FONT>        static private final long serialVersionUID = 1L;<a name="line.134"></a>
<FONT color="green">135</FONT>    <a name="line.135"></a>
<FONT color="green">136</FONT>        /**<a name="line.136"></a>
<FONT color="green">137</FONT>         * trusted promise permission<a name="line.137"></a>
<FONT color="green">138</FONT>         */<a name="line.138"></a>
<FONT color="green">139</FONT>        private   final Token local;<a name="line.139"></a>
<FONT color="green">140</FONT>    <a name="line.140"></a>
<FONT color="green">141</FONT>        /**<a name="line.141"></a>
<FONT color="green">142</FONT>         * raw event loop<a name="line.142"></a>
<FONT color="green">143</FONT>         */<a name="line.143"></a>
<FONT color="green">144</FONT>        protected final Receiver&lt;Promise&lt;?&gt;&gt; enqueue;<a name="line.144"></a>
<FONT color="green">145</FONT>    <a name="line.145"></a>
<FONT color="green">146</FONT>        /**<a name="line.146"></a>
<FONT color="green">147</FONT>         * URI for the event loop<a name="line.147"></a>
<FONT color="green">148</FONT>         */<a name="line.148"></a>
<FONT color="green">149</FONT>        protected final String here;<a name="line.149"></a>
<FONT color="green">150</FONT>    <a name="line.150"></a>
<FONT color="green">151</FONT>        /**<a name="line.151"></a>
<FONT color="green">152</FONT>         * debugging output<a name="line.152"></a>
<FONT color="green">153</FONT>         */<a name="line.153"></a>
<FONT color="green">154</FONT>        public    final Log log;<a name="line.154"></a>
<FONT color="green">155</FONT>    <a name="line.155"></a>
<FONT color="green">156</FONT>        /**<a name="line.156"></a>
<FONT color="green">157</FONT>         * destruct the vat<a name="line.157"></a>
<FONT color="green">158</FONT>         * &lt;p&gt;<a name="line.158"></a>
<FONT color="green">159</FONT>         * call like: {@code destruct.apply(null)}<a name="line.159"></a>
<FONT color="green">160</FONT>         * &lt;/p&gt;<a name="line.160"></a>
<FONT color="green">161</FONT>         */<a name="line.161"></a>
<FONT color="green">162</FONT>        public    final Receiver&lt;?&gt; destruct;<a name="line.162"></a>
<FONT color="green">163</FONT>    <a name="line.163"></a>
<FONT color="green">164</FONT>        /**<a name="line.164"></a>
<FONT color="green">165</FONT>         * mutable statistics about eventual operations<a name="line.165"></a>
<FONT color="green">166</FONT>         */<a name="line.166"></a>
<FONT color="green">167</FONT>        protected final Fulfilled&lt;Stats&gt; stats;<a name="line.167"></a>
<FONT color="green">168</FONT>    <a name="line.168"></a>
<FONT color="green">169</FONT>        /**<a name="line.169"></a>
<FONT color="green">170</FONT>         * Constructs an instance.<a name="line.170"></a>
<FONT color="green">171</FONT>         * @param enqueue   raw event loop<a name="line.171"></a>
<FONT color="green">172</FONT>         * @param here      URI for the event loop<a name="line.172"></a>
<FONT color="green">173</FONT>         * @param log       {@link #log}<a name="line.173"></a>
<FONT color="green">174</FONT>         * @param destruct  {@link #destruct}<a name="line.174"></a>
<FONT color="green">175</FONT>         */<a name="line.175"></a>
<FONT color="green">176</FONT>        public<a name="line.176"></a>
<FONT color="green">177</FONT>        Eventual(final Receiver&lt;Promise&lt;?&gt;&gt; enqueue, final String here,<a name="line.177"></a>
<FONT color="green">178</FONT>                 final Log log, final Receiver&lt;?&gt; destruct) {<a name="line.178"></a>
<FONT color="green">179</FONT>            this.local = new Token();<a name="line.179"></a>
<FONT color="green">180</FONT>            this.enqueue = enqueue;<a name="line.180"></a>
<FONT color="green">181</FONT>            this.here = here;<a name="line.181"></a>
<FONT color="green">182</FONT>            this.log = log;<a name="line.182"></a>
<FONT color="green">183</FONT>            this.destruct = destruct;<a name="line.183"></a>
<FONT color="green">184</FONT>            this.stats = new Fulfilled&lt;Stats&gt;(false, new Stats());<a name="line.184"></a>
<FONT color="green">185</FONT>        }<a name="line.185"></a>
<FONT color="green">186</FONT>    <a name="line.186"></a>
<FONT color="green">187</FONT>        /**<a name="line.187"></a>
<FONT color="green">188</FONT>         * Constructs an instance.<a name="line.188"></a>
<FONT color="green">189</FONT>         * @param enqueue   raw event loop<a name="line.189"></a>
<FONT color="green">190</FONT>         */<a name="line.190"></a>
<FONT color="green">191</FONT>        public<a name="line.191"></a>
<FONT color="green">192</FONT>        Eventual(final Receiver&lt;Promise&lt;?&gt;&gt; enqueue) {<a name="line.192"></a>
<FONT color="green">193</FONT>            this(enqueue, "", new Log(),<a name="line.193"></a>
<FONT color="green">194</FONT>               cast(Receiver.class, new Rejected&lt;Receiver&lt;?&gt;&gt;(null)));<a name="line.194"></a>
<FONT color="green">195</FONT>        }<a name="line.195"></a>
<FONT color="green">196</FONT>    <a name="line.196"></a>
<FONT color="green">197</FONT>        // org.joe_e.Selfless interface<a name="line.197"></a>
<FONT color="green">198</FONT>    <a name="line.198"></a>
<FONT color="green">199</FONT>        public int<a name="line.199"></a>
<FONT color="green">200</FONT>        hashCode() { return 0x1A7E4D0D; }<a name="line.200"></a>
<FONT color="green">201</FONT>    <a name="line.201"></a>
<FONT color="green">202</FONT>        public boolean<a name="line.202"></a>
<FONT color="green">203</FONT>        equals(final Object x) {<a name="line.203"></a>
<FONT color="green">204</FONT>            return x instanceof Eventual &amp;&amp; local == ((Eventual)x).local;<a name="line.204"></a>
<FONT color="green">205</FONT>        }<a name="line.205"></a>
<FONT color="green">206</FONT>    <a name="line.206"></a>
<FONT color="green">207</FONT>        // org.ref_send.promise.Eventual interface<a name="line.207"></a>
<FONT color="green">208</FONT>    <a name="line.208"></a>
<FONT color="green">209</FONT>        /**<a name="line.209"></a>
<FONT color="green">210</FONT>         * Does an eventual conditional operation on a promise.<a name="line.210"></a>
<FONT color="green">211</FONT>         * &lt;p&gt;<a name="line.211"></a>
<FONT color="green">212</FONT>         * The {@code conditional} code block will be notified of the<a name="line.212"></a>
<FONT color="green">213</FONT>         * {@code promise}'s state at most once, in a future event loop turn. If<a name="line.213"></a>
<FONT color="green">214</FONT>         * there is no referent, the {@code conditional}'s {@link Do#reject reject}<a name="line.214"></a>
<FONT color="green">215</FONT>         * method will be called with the reason; otherwise, the<a name="line.215"></a>
<FONT color="green">216</FONT>         * {@link Do#fulfill fulfill} method will be called with either an immediate<a name="line.216"></a>
<FONT color="green">217</FONT>         * reference for a local referent, or an {@linkplain #_ eventual reference}<a name="line.217"></a>
<FONT color="green">218</FONT>         * for a remote referent. For example:<a name="line.218"></a>
<FONT color="green">219</FONT>         * &lt;/p&gt;<a name="line.219"></a>
<FONT color="green">220</FONT>         * &lt;pre&gt;<a name="line.220"></a>
<FONT color="green">221</FONT>         * import static org.ref_send.promise.Eventual.ref;<a name="line.221"></a>
<FONT color="green">222</FONT>         * &amp;hellip;<a name="line.222"></a>
<FONT color="green">223</FONT>         * final Promise&amp;lt;Account&amp;gt; mine = &amp;hellip;<a name="line.223"></a>
<FONT color="green">224</FONT>         * final Promise&amp;lt;Integer&amp;gt; balance =<a name="line.224"></a>
<FONT color="green">225</FONT>         *     _.when(mine, new Do&amp;lt;Account,Promise&amp;lt;Integer&amp;gt;&amp;gt;() {<a name="line.225"></a>
<FONT color="green">226</FONT>         *         public Promise&amp;lt;Integer&amp;gt;<a name="line.226"></a>
<FONT color="green">227</FONT>         *         fulfill(final Account x) { return ref(x.getBalance()); }<a name="line.227"></a>
<FONT color="green">228</FONT>         *     });<a name="line.228"></a>
<FONT color="green">229</FONT>         * &lt;/pre&gt;<a name="line.229"></a>
<FONT color="green">230</FONT>         * &lt;p&gt;<a name="line.230"></a>
<FONT color="green">231</FONT>         * A {@code null} {@code promise} argument is treated like a rejected<a name="line.231"></a>
<FONT color="green">232</FONT>         * promise with a reason of {@link NullPointerException}.<a name="line.232"></a>
<FONT color="green">233</FONT>         * &lt;/p&gt;<a name="line.233"></a>
<FONT color="green">234</FONT>         * &lt;p&gt;<a name="line.234"></a>
<FONT color="green">235</FONT>         * The {@code conditional} in successive calls to this method with the same<a name="line.235"></a>
<FONT color="green">236</FONT>         * {@code promise} will be notified in the same order as the calls were<a name="line.236"></a>
<FONT color="green">237</FONT>         * made.<a name="line.237"></a>
<FONT color="green">238</FONT>         * &lt;/p&gt;<a name="line.238"></a>
<FONT color="green">239</FONT>         * &lt;p&gt;<a name="line.239"></a>
<FONT color="green">240</FONT>         * This method will not throw an {@link Exception}. Neither the<a name="line.240"></a>
<FONT color="green">241</FONT>         * {@code promise}, nor the {@code conditional}, argument will be given the<a name="line.241"></a>
<FONT color="green">242</FONT>         * opportunity to execute in the current event loop turn.<a name="line.242"></a>
<FONT color="green">243</FONT>         * &lt;/p&gt;<a name="line.243"></a>
<FONT color="green">244</FONT>         * @param &lt;P&gt; parameter type<a name="line.244"></a>
<FONT color="green">245</FONT>         * @param &lt;R&gt; return type<a name="line.245"></a>
<FONT color="green">246</FONT>         * @param promise observed promise<a name="line.246"></a>
<FONT color="green">247</FONT>         * @param conditional conditional code block, MUST NOT be {@code null}<a name="line.247"></a>
<FONT color="green">248</FONT>         * @return promise, or {@linkplain #_ eventual reference}, for the<a name="line.248"></a>
<FONT color="green">249</FONT>         *         {@code conditional}'s return, or {@code null} if the<a name="line.249"></a>
<FONT color="green">250</FONT>         *         {@code conditional}'s return type is {@code Void}<a name="line.250"></a>
<FONT color="green">251</FONT>         */<a name="line.251"></a>
<FONT color="green">252</FONT>        public final &lt;P,R&gt; R<a name="line.252"></a>
<FONT color="green">253</FONT>        when(final Promise&lt;P&gt; promise, final Do&lt;P,R&gt; conditional) {<a name="line.253"></a>
<FONT color="green">254</FONT>            try {<a name="line.254"></a>
<FONT color="green">255</FONT>                final Class&lt;?&gt; R= Typedef.raw(returnType(Object.class,conditional));<a name="line.255"></a>
<FONT color="green">256</FONT>                return cast(R, when(null, R, promise, conditional));<a name="line.256"></a>
<FONT color="green">257</FONT>            } catch (final Exception e) { throw new Error(e); }<a name="line.257"></a>
<FONT color="green">258</FONT>        }<a name="line.258"></a>
<FONT color="green">259</FONT>    <a name="line.259"></a>
<FONT color="green">260</FONT>        /**<a name="line.260"></a>
<FONT color="green">261</FONT>         * Does an eventual conditional operation on an<a name="line.261"></a>
<FONT color="green">262</FONT>         * {@linkplain #_ eventual reference}.<a name="line.262"></a>
<FONT color="green">263</FONT>         * &lt;p&gt;<a name="line.263"></a>
<FONT color="green">264</FONT>         * The implementation behavior is the same as that documented for the<a name="line.264"></a>
<FONT color="green">265</FONT>         * promise based {@link #when(Promise, Do) when} statement.<a name="line.265"></a>
<FONT color="green">266</FONT>         * &lt;/p&gt;<a name="line.266"></a>
<FONT color="green">267</FONT>         * @param &lt;P&gt; parameter type<a name="line.267"></a>
<FONT color="green">268</FONT>         * @param &lt;R&gt; return type<a name="line.268"></a>
<FONT color="green">269</FONT>         * @param reference     observed reference<a name="line.269"></a>
<FONT color="green">270</FONT>         * @param conditional   conditional code block, MUST NOT be {@code null}<a name="line.270"></a>
<FONT color="green">271</FONT>         * @return promise, or {@linkplain #_ eventual reference}, for the<a name="line.271"></a>
<FONT color="green">272</FONT>         *         {@code conditional}'s return, or {@code null} if the<a name="line.272"></a>
<FONT color="green">273</FONT>         *         {@code conditional}'s return type is {@code Void}<a name="line.273"></a>
<FONT color="green">274</FONT>         */<a name="line.274"></a>
<FONT color="green">275</FONT>        public final &lt;P,R&gt; R<a name="line.275"></a>
<FONT color="green">276</FONT>        when(final P reference, final Do&lt;P,R&gt; conditional) {<a name="line.276"></a>
<FONT color="green">277</FONT>            try {<a name="line.277"></a>
<FONT color="green">278</FONT>                final Class&lt;?&gt; P = null!=reference?reference.getClass():Void.class;<a name="line.278"></a>
<FONT color="green">279</FONT>                final Class&lt;?&gt; R = Typedef.raw(returnType(P, conditional));<a name="line.279"></a>
<FONT color="green">280</FONT>                return cast(R, when(P, R, ref(reference), conditional));<a name="line.280"></a>
<FONT color="green">281</FONT>            } catch (final Exception e) { throw new Error(e); }<a name="line.281"></a>
<FONT color="green">282</FONT>        }<a name="line.282"></a>
<FONT color="green">283</FONT>    <a name="line.283"></a>
<FONT color="green">284</FONT>        protected final &lt;P,R&gt; Promise&lt;R&gt;<a name="line.284"></a>
<FONT color="green">285</FONT>        when(final Class&lt;?&gt; P, final Class&lt;?&gt; R, final Promise&lt;? extends P&gt; promise,<a name="line.285"></a>
<FONT color="green">286</FONT>             final Do&lt;? super P, ? extends R&gt; conditional) {<a name="line.286"></a>
<FONT color="green">287</FONT>            final Promise&lt;R&gt; r;<a name="line.287"></a>
<FONT color="green">288</FONT>            final Do&lt;? super P,?&gt; forwarder;<a name="line.288"></a>
<FONT color="green">289</FONT>            if (void.class == R || Void.class == R) {<a name="line.289"></a>
<FONT color="green">290</FONT>                r = null;<a name="line.290"></a>
<FONT color="green">291</FONT>                forwarder = conditional;<a name="line.291"></a>
<FONT color="green">292</FONT>            } else {<a name="line.292"></a>
<FONT color="green">293</FONT>                final Deferred&lt;R&gt; x = defer();<a name="line.293"></a>
<FONT color="green">294</FONT>                r = x.promise;<a name="line.294"></a>
<FONT color="green">295</FONT>                forwarder = new Compose&lt;P,R&gt;(conditional, x.resolver);<a name="line.295"></a>
<FONT color="green">296</FONT>            }<a name="line.296"></a>
<FONT color="green">297</FONT>            trust(promise).when(P, forwarder);<a name="line.297"></a>
<FONT color="green">298</FONT>            return r;<a name="line.298"></a>
<FONT color="green">299</FONT>        }<a name="line.299"></a>
<FONT color="green">300</FONT>    <a name="line.300"></a>
<FONT color="green">301</FONT>        /**<a name="line.301"></a>
<FONT color="green">302</FONT>         * Determines a block's return type.<a name="line.302"></a>
<FONT color="green">303</FONT>         * @param P     block's parameter type<a name="line.303"></a>
<FONT color="green">304</FONT>         * @param block block to introspect on<a name="line.304"></a>
<FONT color="green">305</FONT>         * @return {@code block}'s return type<a name="line.305"></a>
<FONT color="green">306</FONT>         */<a name="line.306"></a>
<FONT color="green">307</FONT>        static private Type<a name="line.307"></a>
<FONT color="green">308</FONT>        returnType(final Type P, final Do&lt;?,?&gt; block) {<a name="line.308"></a>
<FONT color="green">309</FONT>            return block instanceof Invoke ?<a name="line.309"></a>
<FONT color="green">310</FONT>                Typedef.bound(((Invoke&lt;?&gt;)block).method.getGenericReturnType(), P) :<a name="line.310"></a>
<FONT color="green">311</FONT>                Typedef.value(DoR, block.getClass());<a name="line.311"></a>
<FONT color="green">312</FONT>        }<a name="line.312"></a>
<FONT color="green">313</FONT>    <a name="line.313"></a>
<FONT color="green">314</FONT>        /**<a name="line.314"></a>
<FONT color="green">315</FONT>         * {@link Do} block return type<a name="line.315"></a>
<FONT color="green">316</FONT>         */<a name="line.316"></a>
<FONT color="green">317</FONT>        static private final TypeVariable&lt;?&gt; DoR = Typedef.var(Do.class, "R");<a name="line.317"></a>
<FONT color="green">318</FONT>    <a name="line.318"></a>
<FONT color="green">319</FONT>        /**<a name="line.319"></a>
<FONT color="green">320</FONT>         * A reified method invocation.<a name="line.320"></a>
<FONT color="green">321</FONT>         * @param &lt;T&gt; target object type<a name="line.321"></a>
<FONT color="green">322</FONT>         */<a name="line.322"></a>
<FONT color="green">323</FONT>        static protected final class<a name="line.323"></a>
<FONT color="green">324</FONT>        Invoke&lt;T&gt; extends Do&lt;T,Object&gt; implements Serializable {<a name="line.324"></a>
<FONT color="green">325</FONT>            static private final long serialVersionUID = 1L;<a name="line.325"></a>
<FONT color="green">326</FONT>    <a name="line.326"></a>
<FONT color="green">327</FONT>            /**<a name="line.327"></a>
<FONT color="green">328</FONT>             * method to invoke<a name="line.328"></a>
<FONT color="green">329</FONT>             */<a name="line.329"></a>
<FONT color="green">330</FONT>            public final Method method;<a name="line.330"></a>
<FONT color="green">331</FONT>    <a name="line.331"></a>
<FONT color="green">332</FONT>            /**<a name="line.332"></a>
<FONT color="green">333</FONT>             * invocation arguments, or {@code null} if none<a name="line.333"></a>
<FONT color="green">334</FONT>             */<a name="line.334"></a>
<FONT color="green">335</FONT>            public final ConstArray&lt;?&gt; argv;<a name="line.335"></a>
<FONT color="green">336</FONT>    <a name="line.336"></a>
<FONT color="green">337</FONT>            /**<a name="line.337"></a>
<FONT color="green">338</FONT>             * Constructs a pending invocation.<a name="line.338"></a>
<FONT color="green">339</FONT>             * @param method    {@link #method}<a name="line.339"></a>
<FONT color="green">340</FONT>             * @param argv      {@link #argv}<a name="line.340"></a>
<FONT color="green">341</FONT>             */<a name="line.341"></a>
<FONT color="green">342</FONT>            public<a name="line.342"></a>
<FONT color="green">343</FONT>            Invoke(final Method method, final ConstArray&lt;?&gt; argv) {<a name="line.343"></a>
<FONT color="green">344</FONT>                this.method = method;<a name="line.344"></a>
<FONT color="green">345</FONT>                this.argv = argv;<a name="line.345"></a>
<FONT color="green">346</FONT>            }<a name="line.346"></a>
<FONT color="green">347</FONT>    <a name="line.347"></a>
<FONT color="green">348</FONT>            public Object<a name="line.348"></a>
<FONT color="green">349</FONT>            fulfill(final T object) throws Exception {<a name="line.349"></a>
<FONT color="green">350</FONT>                // AUDIT: call to untrusted application code<a name="line.350"></a>
<FONT color="green">351</FONT>                return Reflection.invoke(method, object,<a name="line.351"></a>
<FONT color="green">352</FONT>                    null == argv ? null : argv.toArray(new Object[argv.length()]));<a name="line.352"></a>
<FONT color="green">353</FONT>            }<a name="line.353"></a>
<FONT color="green">354</FONT>        }<a name="line.354"></a>
<FONT color="green">355</FONT>    <a name="line.355"></a>
<FONT color="green">356</FONT>        /**<a name="line.356"></a>
<FONT color="green">357</FONT>         * A combined {@link Do} block and return value {@link Resolver}.<a name="line.357"></a>
<FONT color="green">358</FONT>         * @param &lt;P&gt; parameter type<a name="line.358"></a>
<FONT color="green">359</FONT>         * @param &lt;R&gt; return type<a name="line.359"></a>
<FONT color="green">360</FONT>         */<a name="line.360"></a>
<FONT color="green">361</FONT>        static protected final class<a name="line.361"></a>
<FONT color="green">362</FONT>        Compose&lt;P,R&gt; extends Do&lt;P,Void&gt; implements Serializable {<a name="line.362"></a>
<FONT color="green">363</FONT>            static private final long serialVersionUID = 1L;<a name="line.363"></a>
<FONT color="green">364</FONT>    <a name="line.364"></a>
<FONT color="green">365</FONT>            /**<a name="line.365"></a>
<FONT color="green">366</FONT>             * conditional code block to execute<a name="line.366"></a>
<FONT color="green">367</FONT>             */<a name="line.367"></a>
<FONT color="green">368</FONT>            public final Do&lt;? super P,? extends R&gt; conditional;<a name="line.368"></a>
<FONT color="green">369</FONT>    <a name="line.369"></a>
<FONT color="green">370</FONT>            /**<a name="line.370"></a>
<FONT color="green">371</FONT>             * return value resolver<a name="line.371"></a>
<FONT color="green">372</FONT>             */<a name="line.372"></a>
<FONT color="green">373</FONT>            public final Resolver&lt;R&gt; resolver;<a name="line.373"></a>
<FONT color="green">374</FONT>    <a name="line.374"></a>
<FONT color="green">375</FONT>            /**<a name="line.375"></a>
<FONT color="green">376</FONT>             * Constructs an instance.<a name="line.376"></a>
<FONT color="green">377</FONT>             * @param conditional   {@link #conditional}<a name="line.377"></a>
<FONT color="green">378</FONT>             * @param resolver      {@link #resolver}<a name="line.378"></a>
<FONT color="green">379</FONT>             */<a name="line.379"></a>
<FONT color="green">380</FONT>            public<a name="line.380"></a>
<FONT color="green">381</FONT>            Compose(final Do&lt;? super P, ? extends R&gt; conditional,<a name="line.381"></a>
<FONT color="green">382</FONT>                    final Resolver&lt;R&gt; resolver) {<a name="line.382"></a>
<FONT color="green">383</FONT>                this.conditional = conditional;<a name="line.383"></a>
<FONT color="green">384</FONT>                this.resolver = resolver;<a name="line.384"></a>
<FONT color="green">385</FONT>            }<a name="line.385"></a>
<FONT color="green">386</FONT>    <a name="line.386"></a>
<FONT color="green">387</FONT>            // org.ref_send.promise.Do interface<a name="line.387"></a>
<FONT color="green">388</FONT>    <a name="line.388"></a>
<FONT color="green">389</FONT>            public Void<a name="line.389"></a>
<FONT color="green">390</FONT>            fulfill(final P a) {<a name="line.390"></a>
<FONT color="green">391</FONT>                final R r;<a name="line.391"></a>
<FONT color="green">392</FONT>                try {<a name="line.392"></a>
<FONT color="green">393</FONT>                    r = conditional.fulfill(a);<a name="line.393"></a>
<FONT color="green">394</FONT>                } catch (final Exception e) {<a name="line.394"></a>
<FONT color="green">395</FONT>                    resolver.reject(e);<a name="line.395"></a>
<FONT color="green">396</FONT>                    return null;<a name="line.396"></a>
<FONT color="green">397</FONT>                }<a name="line.397"></a>
<FONT color="green">398</FONT>                resolver.apply(r);<a name="line.398"></a>
<FONT color="green">399</FONT>                return null;<a name="line.399"></a>
<FONT color="green">400</FONT>            }<a name="line.400"></a>
<FONT color="green">401</FONT>    <a name="line.401"></a>
<FONT color="green">402</FONT>            public Void<a name="line.402"></a>
<FONT color="green">403</FONT>            reject(final Exception reason) {<a name="line.403"></a>
<FONT color="green">404</FONT>                final R r;<a name="line.404"></a>
<FONT color="green">405</FONT>                try {<a name="line.405"></a>
<FONT color="green">406</FONT>                    r = conditional.reject(reason);<a name="line.406"></a>
<FONT color="green">407</FONT>                } catch (final Exception e) {<a name="line.407"></a>
<FONT color="green">408</FONT>                    resolver.reject(e);<a name="line.408"></a>
<FONT color="green">409</FONT>                    return null;<a name="line.409"></a>
<FONT color="green">410</FONT>                }<a name="line.410"></a>
<FONT color="green">411</FONT>                resolver.apply(r);<a name="line.411"></a>
<FONT color="green">412</FONT>                return null;<a name="line.412"></a>
<FONT color="green">413</FONT>            }<a name="line.413"></a>
<FONT color="green">414</FONT>        }<a name="line.414"></a>
<FONT color="green">415</FONT>    <a name="line.415"></a>
<FONT color="green">416</FONT>        private final &lt;T&gt; Local&lt;T&gt;<a name="line.416"></a>
<FONT color="green">417</FONT>        trust(final Promise&lt;T&gt; untrusted) {<a name="line.417"></a>
<FONT color="green">418</FONT>            return trusted(untrusted) ?<a name="line.418"></a>
<FONT color="green">419</FONT>                (Local&lt;T&gt;)untrusted : new Enqueue&lt;T&gt;(untrusted);<a name="line.419"></a>
<FONT color="green">420</FONT>        }<a name="line.420"></a>
<FONT color="green">421</FONT>    <a name="line.421"></a>
<FONT color="green">422</FONT>        protected final boolean<a name="line.422"></a>
<FONT color="green">423</FONT>        trusted(final Object untrusted) {<a name="line.423"></a>
<FONT color="green">424</FONT>            return untrusted instanceof Local &amp;&amp;<a name="line.424"></a>
<FONT color="green">425</FONT>                   local == ((Local&lt;?&gt;)untrusted).getScope().local;<a name="line.425"></a>
<FONT color="green">426</FONT>        }<a name="line.426"></a>
<FONT color="green">427</FONT>    <a name="line.427"></a>
<FONT color="green">428</FONT>        /**<a name="line.428"></a>
<FONT color="green">429</FONT>         * An abstract base class for a promise implementation that is scoped to a<a name="line.429"></a>
<FONT color="green">430</FONT>         * particular event queue.<a name="line.430"></a>
<FONT color="green">431</FONT>         * @param &lt;T&gt; referent type<a name="line.431"></a>
<FONT color="green">432</FONT>         */<a name="line.432"></a>
<FONT color="green">433</FONT>        protected abstract class<a name="line.433"></a>
<FONT color="green">434</FONT>        Local&lt;T&gt; implements Promise&lt;T&gt;, InvocationHandler, Selfless, Serializable {<a name="line.434"></a>
<FONT color="green">435</FONT>            static private final long serialVersionUID = 1L;<a name="line.435"></a>
<FONT color="green">436</FONT>    <a name="line.436"></a>
<FONT color="green">437</FONT>            protected final Eventual<a name="line.437"></a>
<FONT color="green">438</FONT>            getScope() { return Eventual.this; }<a name="line.438"></a>
<FONT color="green">439</FONT>    <a name="line.439"></a>
<FONT color="green">440</FONT>            // org.joe_e.Selfless interface<a name="line.440"></a>
<FONT color="green">441</FONT>    <a name="line.441"></a>
<FONT color="green">442</FONT>            public abstract boolean<a name="line.442"></a>
<FONT color="green">443</FONT>            equals(Object x);<a name="line.443"></a>
<FONT color="green">444</FONT>    <a name="line.444"></a>
<FONT color="green">445</FONT>            public abstract int<a name="line.445"></a>
<FONT color="green">446</FONT>            hashCode();<a name="line.446"></a>
<FONT color="green">447</FONT>    <a name="line.447"></a>
<FONT color="green">448</FONT>            // java.lang.reflect.InvocationHandler interface<a name="line.448"></a>
<FONT color="green">449</FONT>    <a name="line.449"></a>
<FONT color="green">450</FONT>            /**<a name="line.450"></a>
<FONT color="green">451</FONT>             * Forwards a Java language invocation.<a name="line.451"></a>
<FONT color="green">452</FONT>             * @param proxy     eventual reference<a name="line.452"></a>
<FONT color="green">453</FONT>             * @param method    method to invoke<a name="line.453"></a>
<FONT color="green">454</FONT>             * @param args      each invocation argument<a name="line.454"></a>
<FONT color="green">455</FONT>             * @return eventual reference for the invocation return<a name="line.455"></a>
<FONT color="green">456</FONT>             */<a name="line.456"></a>
<FONT color="green">457</FONT>            public final Object<a name="line.457"></a>
<FONT color="green">458</FONT>            invoke(final Object proxy, final Method method,<a name="line.458"></a>
<FONT color="green">459</FONT>                   final Object[] args) throws Exception {<a name="line.459"></a>
<FONT color="green">460</FONT>                if (Object.class == method.getDeclaringClass()) {<a name="line.460"></a>
<FONT color="green">461</FONT>                    if ("equals".equals(method.getName())) {<a name="line.461"></a>
<FONT color="green">462</FONT>                        return args[0] instanceof Proxy &amp;&amp;<a name="line.462"></a>
<FONT color="green">463</FONT>                            proxy.getClass() == args[0].getClass() &amp;&amp;<a name="line.463"></a>
<FONT color="green">464</FONT>                            equals(Proxies.getHandler((Proxy)args[0]));<a name="line.464"></a>
<FONT color="green">465</FONT>                    } else {<a name="line.465"></a>
<FONT color="green">466</FONT>                        return Reflection.invoke(method, this, args);<a name="line.466"></a>
<FONT color="green">467</FONT>                    }<a name="line.467"></a>
<FONT color="green">468</FONT>                }<a name="line.468"></a>
<FONT color="green">469</FONT>                try {<a name="line.469"></a>
<FONT color="green">470</FONT>                    final Class&lt;?&gt; T = proxy.getClass();<a name="line.470"></a>
<FONT color="green">471</FONT>                    final Class&lt;?&gt; R =<a name="line.471"></a>
<FONT color="green">472</FONT>                        Typedef.raw(Typedef.bound(method.getGenericReturnType(),T));<a name="line.472"></a>
<FONT color="green">473</FONT>                    final Tail&lt;?&gt; r =<a name="line.473"></a>
<FONT color="green">474</FONT>                        (Tail&lt;?&gt;)Eventual.this.when(T, R, this, new Invoke&lt;T&gt;(<a name="line.474"></a>
<FONT color="green">475</FONT>                            method, null == args ? null : ConstArray.array(args)));<a name="line.475"></a>
<FONT color="green">476</FONT>                    if (null == r) { return null; }<a name="line.476"></a>
<FONT color="green">477</FONT>    <a name="line.477"></a>
<FONT color="green">478</FONT>                    // implementation might have already resolved a pipeline promise<a name="line.478"></a>
<FONT color="green">479</FONT>                    final State&lt;?&gt; cell = near(r.state);<a name="line.479"></a>
<FONT color="green">480</FONT>                    return cast(R, cell.resolved ? cell.value : r);<a name="line.480"></a>
<FONT color="green">481</FONT>                } catch (final Exception e) { throw new Error(e); }<a name="line.481"></a>
<FONT color="green">482</FONT>            }<a name="line.482"></a>
<FONT color="green">483</FONT>    <a name="line.483"></a>
<FONT color="green">484</FONT>            // org.ref_send.promise.Promise interface<a name="line.484"></a>
<FONT color="green">485</FONT>    <a name="line.485"></a>
<FONT color="green">486</FONT>            public abstract T<a name="line.486"></a>
<FONT color="green">487</FONT>            call() throws Exception;<a name="line.487"></a>
<FONT color="green">488</FONT>    <a name="line.488"></a>
<FONT color="green">489</FONT>            // org.ref_send.promise.Local interface<a name="line.489"></a>
<FONT color="green">490</FONT>    <a name="line.490"></a>
<FONT color="green">491</FONT>            /**<a name="line.491"></a>
<FONT color="green">492</FONT>             * Shortens the promise chain by one link.<a name="line.492"></a>
<FONT color="green">493</FONT>             */<a name="line.493"></a>
<FONT color="green">494</FONT>            public abstract Object<a name="line.494"></a>
<FONT color="green">495</FONT>            shorten() throws Unresolved;<a name="line.495"></a>
<FONT color="green">496</FONT>    <a name="line.496"></a>
<FONT color="green">497</FONT>            /**<a name="line.497"></a>
<FONT color="green">498</FONT>             * Notifies an observer in a future event loop turn.<a name="line.498"></a>
<FONT color="green">499</FONT>             * @param T         concrete referent type, {@code null} if not known<a name="line.499"></a>
<FONT color="green">500</FONT>             * @param observer  promise observer<a name="line.500"></a>
<FONT color="green">501</FONT>             */<a name="line.501"></a>
<FONT color="green">502</FONT>            public abstract void<a name="line.502"></a>
<FONT color="green">503</FONT>            when(Class&lt;?&gt; T, Do&lt;? super T,?&gt; observer);<a name="line.503"></a>
<FONT color="green">504</FONT>        }<a name="line.504"></a>
<FONT color="green">505</FONT>    <a name="line.505"></a>
<FONT color="green">506</FONT>        private final class<a name="line.506"></a>
<FONT color="green">507</FONT>        Enqueue&lt;T&gt; extends Local&lt;T&gt; {<a name="line.507"></a>
<FONT color="green">508</FONT>            static private final long serialVersionUID = 1L;<a name="line.508"></a>
<FONT color="green">509</FONT>    <a name="line.509"></a>
<FONT color="green">510</FONT>            final Promise&lt;T&gt; untrusted;<a name="line.510"></a>
<FONT color="green">511</FONT>    <a name="line.511"></a>
<FONT color="green">512</FONT>            Enqueue(final Promise&lt;T&gt; untrusted) {<a name="line.512"></a>
<FONT color="green">513</FONT>                this.untrusted = untrusted;<a name="line.513"></a>
<FONT color="green">514</FONT>            }<a name="line.514"></a>
<FONT color="green">515</FONT>    <a name="line.515"></a>
<FONT color="green">516</FONT>            public int<a name="line.516"></a>
<FONT color="green">517</FONT>            hashCode() { return 0x174057ED; }<a name="line.517"></a>
<FONT color="green">518</FONT>    <a name="line.518"></a>
<FONT color="green">519</FONT>            public boolean<a name="line.519"></a>
<FONT color="green">520</FONT>            equals(final Object x) {<a name="line.520"></a>
<FONT color="green">521</FONT>                return x instanceof Enqueue &amp;&amp;<a name="line.521"></a>
<FONT color="green">522</FONT>                    Eventual.this.equals(((Enqueue&lt;?&gt;)x).getScope()) &amp;&amp;<a name="line.522"></a>
<FONT color="green">523</FONT>                    (null != untrusted ?<a name="line.523"></a>
<FONT color="green">524</FONT>                        untrusted.equals(((Enqueue&lt;?&gt;)x).untrusted) :<a name="line.524"></a>
<FONT color="green">525</FONT>                        null == ((Enqueue&lt;?&gt;)x).untrusted);<a name="line.525"></a>
<FONT color="green">526</FONT>            }<a name="line.526"></a>
<FONT color="green">527</FONT>    <a name="line.527"></a>
<FONT color="green">528</FONT>            public T<a name="line.528"></a>
<FONT color="green">529</FONT>            call() throws Exception { return untrusted.call(); }<a name="line.529"></a>
<FONT color="green">530</FONT>    <a name="line.530"></a>
<FONT color="green">531</FONT>            public Object<a name="line.531"></a>
<FONT color="green">532</FONT>            shorten() { return this; }<a name="line.532"></a>
<FONT color="green">533</FONT>    <a name="line.533"></a>
<FONT color="green">534</FONT>            public void<a name="line.534"></a>
<FONT color="green">535</FONT>            when(final Class&lt;?&gt; T, final Do&lt;? super T, ?&gt; observer) {<a name="line.535"></a>
<FONT color="green">536</FONT>                final long id = near(stats).newTask();<a name="line.536"></a>
<FONT color="green">537</FONT>                class Sample extends Struct implements Promise&lt;Void&gt;, Serializable {<a name="line.537"></a>
<FONT color="green">538</FONT>                    static private final long serialVersionUID = 1L;<a name="line.538"></a>
<FONT color="green">539</FONT>    <a name="line.539"></a>
<FONT color="green">540</FONT>                    public Void<a name="line.540"></a>
<FONT color="green">541</FONT>                    call() throws Exception {<a name="line.541"></a>
<FONT color="green">542</FONT>                        // AUDIT: call to untrusted application code<a name="line.542"></a>
<FONT color="green">543</FONT>                        try {<a name="line.543"></a>
<FONT color="green">544</FONT>                            sample(untrusted, observer, log, here + "#t" + id);<a name="line.544"></a>
<FONT color="green">545</FONT>                        } catch (final Exception e) {<a name="line.545"></a>
<FONT color="green">546</FONT>                            log.problem(e);<a name="line.546"></a>
<FONT color="green">547</FONT>                            throw e;<a name="line.547"></a>
<FONT color="green">548</FONT>                        }<a name="line.548"></a>
<FONT color="green">549</FONT>                        return null;<a name="line.549"></a>
<FONT color="green">550</FONT>                    }<a name="line.550"></a>
<FONT color="green">551</FONT>                }<a name="line.551"></a>
<FONT color="green">552</FONT>                enqueue.apply(new Sample());<a name="line.552"></a>
<FONT color="green">553</FONT>                log.sent(here + "#t" + id);<a name="line.553"></a>
<FONT color="green">554</FONT>            }<a name="line.554"></a>
<FONT color="green">555</FONT>        }<a name="line.555"></a>
<FONT color="green">556</FONT>    <a name="line.556"></a>
<FONT color="green">557</FONT>        static private final Method fulfill;<a name="line.557"></a>
<FONT color="green">558</FONT>        static {<a name="line.558"></a>
<FONT color="green">559</FONT>            try {<a name="line.559"></a>
<FONT color="green">560</FONT>                fulfill = Reflection.method(Do.class, "fulfill", Object.class);<a name="line.560"></a>
<FONT color="green">561</FONT>            } catch (final NoSuchMethodException e) {throw new NoSuchMethodError();}<a name="line.561"></a>
<FONT color="green">562</FONT>        }<a name="line.562"></a>
<FONT color="green">563</FONT>    <a name="line.563"></a>
<FONT color="green">564</FONT>        static private final Method reject;<a name="line.564"></a>
<FONT color="green">565</FONT>        static {<a name="line.565"></a>
<FONT color="green">566</FONT>            try {<a name="line.566"></a>
<FONT color="green">567</FONT>                reject = Reflection.method(Do.class, "reject", Exception.class);<a name="line.567"></a>
<FONT color="green">568</FONT>            } catch (final NoSuchMethodException e) {throw new NoSuchMethodError();}<a name="line.568"></a>
<FONT color="green">569</FONT>        }<a name="line.569"></a>
<FONT color="green">570</FONT>    <a name="line.570"></a>
<FONT color="green">571</FONT>        /**<a name="line.571"></a>
<FONT color="green">572</FONT>         * A recognizable exception to avoid logging an ignored null resolution.<a name="line.572"></a>
<FONT color="green">573</FONT>         */<a name="line.573"></a>
<FONT color="green">574</FONT>        static private final NullPointerException VOID = new NullPointerException();<a name="line.574"></a>
<FONT color="green">575</FONT>    <a name="line.575"></a>
<FONT color="green">576</FONT>        static protected &lt;P,R&gt; R<a name="line.576"></a>
<FONT color="green">577</FONT>        sample(final Promise&lt;? extends P&gt; promise,<a name="line.577"></a>
<FONT color="green">578</FONT>               final Do&lt;? super P, ? extends R&gt; observer,<a name="line.578"></a>
<FONT color="green">579</FONT>               final Log log, final String message) throws Exception {<a name="line.579"></a>
<FONT color="green">580</FONT>            final P a;<a name="line.580"></a>
<FONT color="green">581</FONT>            try {<a name="line.581"></a>
<FONT color="green">582</FONT>                if (null == promise) { throw VOID; }<a name="line.582"></a>
<FONT color="green">583</FONT>                a = promise.call();<a name="line.583"></a>
<FONT color="green">584</FONT>    <a name="line.584"></a>
<FONT color="green">585</FONT>                // ensure the called value is not one that is<a name="line.585"></a>
<FONT color="green">586</FONT>                // expected to be handled as a rejection<a name="line.586"></a>
<FONT color="green">587</FONT>                if (null == a) { throw VOID; }<a name="line.587"></a>
<FONT color="green">588</FONT>                final Promise&lt;?&gt; p = ref(a);<a name="line.588"></a>
<FONT color="green">589</FONT>                if (p instanceof Rejected) { p.call(); }<a name="line.589"></a>
<FONT color="green">590</FONT>            } catch (final Exception reason) {<a name="line.590"></a>
<FONT color="green">591</FONT>                final @SuppressWarnings({ "rawtypes", "unchecked" }) Class&lt;?&gt; c =<a name="line.591"></a>
<FONT color="green">592</FONT>                    (observer instanceof Compose ? ((Compose)observer).conditional :<a name="line.592"></a>
<FONT color="green">593</FONT>                                                   observer).getClass();<a name="line.593"></a>
<FONT color="green">594</FONT>                log.got(message, c, reject);<a name="line.594"></a>
<FONT color="green">595</FONT>                try {<a name="line.595"></a>
<FONT color="green">596</FONT>                    return observer.reject(reason);<a name="line.596"></a>
<FONT color="green">597</FONT>                } catch (final NullPointerException shadow) {<a name="line.597"></a>
<FONT color="green">598</FONT>                    if (VOID.equals(shadow)) { return null; }<a name="line.598"></a>
<FONT color="green">599</FONT>                    throw shadow;<a name="line.599"></a>
<FONT color="green">600</FONT>                }<a name="line.600"></a>
<FONT color="green">601</FONT>            }<a name="line.601"></a>
<FONT color="green">602</FONT>            final Method m;<a name="line.602"></a>
<FONT color="green">603</FONT>            final Class&lt;?&gt; c; {<a name="line.603"></a>
<FONT color="green">604</FONT>                final @SuppressWarnings({ "rawtypes", "unchecked" }) Do inner =<a name="line.604"></a>
<FONT color="green">605</FONT>                    observer instanceof Compose ?<a name="line.605"></a>
<FONT color="green">606</FONT>                            ((Compose)observer).conditional : observer;<a name="line.606"></a>
<FONT color="green">607</FONT>                if (inner instanceof Invoke) {<a name="line.607"></a>
<FONT color="green">608</FONT>                    m = ((Invoke&lt;?&gt;)inner).method;<a name="line.608"></a>
<FONT color="green">609</FONT>                    c = a.getClass();<a name="line.609"></a>
<FONT color="green">610</FONT>                } else {<a name="line.610"></a>
<FONT color="green">611</FONT>                    m = fulfill;<a name="line.611"></a>
<FONT color="green">612</FONT>                    c = inner.getClass();<a name="line.612"></a>
<FONT color="green">613</FONT>                }<a name="line.613"></a>
<FONT color="green">614</FONT>            }<a name="line.614"></a>
<FONT color="green">615</FONT>            log.got(message, c, m);<a name="line.615"></a>
<FONT color="green">616</FONT>            return observer.fulfill(a);<a name="line.616"></a>
<FONT color="green">617</FONT>        }<a name="line.617"></a>
<FONT color="green">618</FONT>    <a name="line.618"></a>
<FONT color="green">619</FONT>        /**<a name="line.619"></a>
<FONT color="green">620</FONT>         * A registered promise observer.<a name="line.620"></a>
<FONT color="green">621</FONT>         * @param &lt;T&gt; referent type<a name="line.621"></a>
<FONT color="green">622</FONT>         */<a name="line.622"></a>
<FONT color="green">623</FONT>        static protected final class<a name="line.623"></a>
<FONT color="green">624</FONT>        When&lt;T&gt; implements Equatable, Serializable {<a name="line.624"></a>
<FONT color="green">625</FONT>            static private final long serialVersionUID = 1L;<a name="line.625"></a>
<FONT color="green">626</FONT>    <a name="line.626"></a>
<FONT color="green">627</FONT>            long condition;             // id for the corresponding promise<a name="line.627"></a>
<FONT color="green">628</FONT>            long message;               // id for this when block<a name="line.628"></a>
<FONT color="green">629</FONT>            Do&lt;? super T,?&gt; observer;   // client's when block code<a name="line.629"></a>
<FONT color="green">630</FONT>            Promise&lt;When&lt;T&gt;&gt; next;      // next when block registered on the promise<a name="line.630"></a>
<FONT color="green">631</FONT>        }<a name="line.631"></a>
<FONT color="green">632</FONT>    <a name="line.632"></a>
<FONT color="green">633</FONT>        /**<a name="line.633"></a>
<FONT color="green">634</FONT>         * Executes the next Do block registered on the promise.<a name="line.634"></a>
<FONT color="green">635</FONT>         */<a name="line.635"></a>
<FONT color="green">636</FONT>        private final class<a name="line.636"></a>
<FONT color="green">637</FONT>        Forward&lt;T&gt; extends Struct implements Promise&lt;Void&gt;, Serializable {<a name="line.637"></a>
<FONT color="green">638</FONT>            static private final long serialVersionUID = 1L;<a name="line.638"></a>
<FONT color="green">639</FONT>    <a name="line.639"></a>
<FONT color="green">640</FONT>            private final boolean ignored;              // value ignored so far?<a name="line.640"></a>
<FONT color="green">641</FONT>            private final long condition;               // corresponding promise id<a name="line.641"></a>
<FONT color="green">642</FONT>            private final Promise&lt;When&lt;T&gt;&gt; pending;     // when block to run<a name="line.642"></a>
<FONT color="green">643</FONT>            private final Class&lt;?&gt; T;                   // referent type of promise<a name="line.643"></a>
<FONT color="green">644</FONT>            private final Promise&lt;? extends T&gt; value;   // resolved value of promise<a name="line.644"></a>
<FONT color="green">645</FONT>    <a name="line.645"></a>
<FONT color="green">646</FONT>            Forward(final boolean ignored,<a name="line.646"></a>
<FONT color="green">647</FONT>                    final long condition, final Promise&lt;When&lt;T&gt;&gt; pending,<a name="line.647"></a>
<FONT color="green">648</FONT>                    final Class&lt;?&gt; T, final Promise&lt;? extends T&gt; value) {<a name="line.648"></a>
<FONT color="green">649</FONT>                this.ignored = ignored;<a name="line.649"></a>
<FONT color="green">650</FONT>                this.condition = condition;<a name="line.650"></a>
<FONT color="green">651</FONT>                this.pending = pending;<a name="line.651"></a>
<FONT color="green">652</FONT>                this.T = T;<a name="line.652"></a>
<FONT color="green">653</FONT>                this.value = value;<a name="line.653"></a>
<FONT color="green">654</FONT>            }<a name="line.654"></a>
<FONT color="green">655</FONT>    <a name="line.655"></a>
<FONT color="green">656</FONT>            public Void<a name="line.656"></a>
<FONT color="green">657</FONT>            call() throws Exception {<a name="line.657"></a>
<FONT color="green">658</FONT>                final long message;<a name="line.658"></a>
<FONT color="green">659</FONT>                final Do&lt;? super T,?&gt; observer;<a name="line.659"></a>
<FONT color="green">660</FONT>                final Promise&lt;When&lt;T&gt;&gt; next; {<a name="line.660"></a>
<FONT color="green">661</FONT>                    final When&lt;T&gt; block;<a name="line.661"></a>
<FONT color="green">662</FONT>                    try {<a name="line.662"></a>
<FONT color="green">663</FONT>                        block = pending.call();<a name="line.663"></a>
<FONT color="green">664</FONT>                    } catch (final Exception e) {<a name="line.664"></a>
<FONT color="green">665</FONT>                        /*<a name="line.665"></a>
<FONT color="green">666</FONT>                         * There was a problem loading the saved when block. Ignore<a name="line.666"></a>
<FONT color="green">667</FONT>                         * it and all subsequent when blocks on this promise.<a name="line.667"></a>
<FONT color="green">668</FONT>                         */<a name="line.668"></a>
<FONT color="green">669</FONT>                        log.problem(e);<a name="line.669"></a>
<FONT color="green">670</FONT>                        throw e;<a name="line.670"></a>
<FONT color="green">671</FONT>                    }<a name="line.671"></a>
<FONT color="green">672</FONT>                    if (condition != block.condition) { return null; } // been done<a name="line.672"></a>
<FONT color="green">673</FONT>    <a name="line.673"></a>
<FONT color="green">674</FONT>                    // free the block, thus ensuring it is not run again<a name="line.674"></a>
<FONT color="green">675</FONT>                    message     = block.message;<a name="line.675"></a>
<FONT color="green">676</FONT>                    observer    = block.observer;<a name="line.676"></a>
<FONT color="green">677</FONT>                    next        = block.next;<a name="line.677"></a>
<FONT color="green">678</FONT>                    near(stats).freeWhen(pending, block);<a name="line.678"></a>
<FONT color="green">679</FONT>                }<a name="line.679"></a>
<FONT color="green">680</FONT>    <a name="line.680"></a>
<FONT color="green">681</FONT>                if (null != next) {<a name="line.681"></a>
<FONT color="green">682</FONT>                    enqueue.apply(new Forward&lt;T&gt;(false, condition, next, T, value));<a name="line.682"></a>
<FONT color="green">683</FONT>                    try {<a name="line.683"></a>
<FONT color="green">684</FONT>                        if (trusted(value)) {<a name="line.684"></a>
<FONT color="green">685</FONT>                            log.got(here + "#w" + message, null, null);<a name="line.685"></a>
<FONT color="green">686</FONT>                            final @SuppressWarnings("unchecked") Local&lt;? extends T&gt;<a name="line.686"></a>
<FONT color="green">687</FONT>                                promise = (Local&lt;? extends T&gt;)value;<a name="line.687"></a>
<FONT color="green">688</FONT>                            promise.when(T, observer);<a name="line.688"></a>
<FONT color="green">689</FONT>                        } else {<a name="line.689"></a>
<FONT color="green">690</FONT>                            // AUDIT: call to untrusted application code<a name="line.690"></a>
<FONT color="green">691</FONT>                            sample(value, observer, log, here + "#w" + message);<a name="line.691"></a>
<FONT color="green">692</FONT>                        }<a name="line.692"></a>
<FONT color="green">693</FONT>                    } catch (final Exception e) {<a name="line.693"></a>
<FONT color="green">694</FONT>                        log.problem(e);<a name="line.694"></a>
<FONT color="green">695</FONT>                        throw e;<a name="line.695"></a>
<FONT color="green">696</FONT>                    }<a name="line.696"></a>
<FONT color="green">697</FONT>                } else if (ignored &amp;&amp; value instanceof Rejected) {<a name="line.697"></a>
<FONT color="green">698</FONT>                    /*<a name="line.698"></a>
<FONT color="green">699</FONT>                     * No when block has been queued on this promise, so this<a name="line.699"></a>
<FONT color="green">700</FONT>                     * rejection will go unnoticed by the application code. To make<a name="line.700"></a>
<FONT color="green">701</FONT>                     * the exception show up in the log, create a dummy when block<a name="line.701"></a>
<FONT color="green">702</FONT>                     * to log the problem. This dummy when block has the unusual<a name="line.702"></a>
<FONT color="green">703</FONT>                     * nature of being a message that is received before it is sent.<a name="line.703"></a>
<FONT color="green">704</FONT>                     */<a name="line.704"></a>
<FONT color="green">705</FONT>                    final Exception e = ((Rejected&lt;?&gt;)value).reason;<a name="line.705"></a>
<FONT color="green">706</FONT>                    log.got(here + "#w" + message, null, null);<a name="line.706"></a>
<FONT color="green">707</FONT>                    log.sentIf(false, here+"#w"+message, here+"#p"+condition);<a name="line.707"></a>
<FONT color="green">708</FONT>                    log.problem(e);<a name="line.708"></a>
<FONT color="green">709</FONT>                    throw e;<a name="line.709"></a>
<FONT color="green">710</FONT>                }<a name="line.710"></a>
<FONT color="green">711</FONT>                return null;<a name="line.711"></a>
<FONT color="green">712</FONT>            }<a name="line.712"></a>
<FONT color="green">713</FONT>        }<a name="line.713"></a>
<FONT color="green">714</FONT>    <a name="line.714"></a>
<FONT color="green">715</FONT>        private final class<a name="line.715"></a>
<FONT color="green">716</FONT>        State&lt;T&gt; implements Serializable {<a name="line.716"></a>
<FONT color="green">717</FONT>            static private final long serialVersionUID = 1L;<a name="line.717"></a>
<FONT color="green">718</FONT>    <a name="line.718"></a>
<FONT color="green">719</FONT>            final long condition;               // id of this promise<a name="line.719"></a>
<FONT color="green">720</FONT>                  Promise&lt;When&lt;T&gt;&gt; back;        // observer list sentinel<a name="line.720"></a>
<FONT color="green">721</FONT>    <a name="line.721"></a>
<FONT color="green">722</FONT>                  boolean resolved;             // Is resolved?<a name="line.722"></a>
<FONT color="green">723</FONT>                  Class&lt;?&gt; T;                   // concrete referent type<a name="line.723"></a>
<FONT color="green">724</FONT>                  Promise&lt;? extends T&gt; value;   // resolved value<a name="line.724"></a>
<FONT color="green">725</FONT>    <a name="line.725"></a>
<FONT color="green">726</FONT>            State(final long condition, final Promise&lt;When&lt;T&gt;&gt; back) {<a name="line.726"></a>
<FONT color="green">727</FONT>                this.condition = condition;<a name="line.727"></a>
<FONT color="green">728</FONT>                this.back = back;<a name="line.728"></a>
<FONT color="green">729</FONT>            }<a name="line.729"></a>
<FONT color="green">730</FONT>    <a name="line.730"></a>
<FONT color="green">731</FONT>            protected void<a name="line.731"></a>
<FONT color="green">732</FONT>            observe(final Do&lt;? super T,?&gt; observer) {<a name="line.732"></a>
<FONT color="green">733</FONT>                final boolean call = observer instanceof Compose &amp;&amp;<a name="line.733"></a>
<FONT color="green">734</FONT>                    ((Compose&lt;?,?&gt;)observer).conditional instanceof Invoke;<a name="line.734"></a>
<FONT color="green">735</FONT>                final When&lt;T&gt; block = near(back);<a name="line.735"></a>
<FONT color="green">736</FONT>                if (condition == block.condition) {<a name="line.736"></a>
<FONT color="green">737</FONT>                    log.sentIf(call, here+"#w"+block.message, here+"#p"+condition);<a name="line.737"></a>
<FONT color="green">738</FONT>                    block.observer = observer;<a name="line.738"></a>
<FONT color="green">739</FONT>                    back = block.next = near(stats).allocWhen(condition);<a name="line.739"></a>
<FONT color="green">740</FONT>                } else {<a name="line.740"></a>
<FONT color="green">741</FONT>                    /*<a name="line.741"></a>
<FONT color="green">742</FONT>                     * Promise is already resolved and all previously registered<a name="line.742"></a>
<FONT color="green">743</FONT>                     * observers run. Register the observer on the resolved value,<a name="line.743"></a>
<FONT color="green">744</FONT>                     * but using a separate turn so that we don't lose the causality<a name="line.744"></a>
<FONT color="green">745</FONT>                     * chain from this promise to the resolved value.<a name="line.745"></a>
<FONT color="green">746</FONT>                     */<a name="line.746"></a>
<FONT color="green">747</FONT>                    final long task = near(stats).newTask();<a name="line.747"></a>
<FONT color="green">748</FONT>                    class Fwd extends Struct implements Promise&lt;Void&gt;, Serializable{<a name="line.748"></a>
<FONT color="green">749</FONT>                        static private final long serialVersionUID = 1L;<a name="line.749"></a>
<FONT color="green">750</FONT>    <a name="line.750"></a>
<FONT color="green">751</FONT>                        public Void<a name="line.751"></a>
<FONT color="green">752</FONT>                        call() {<a name="line.752"></a>
<FONT color="green">753</FONT>                            log.got(here + "#t" + task, null, null);<a name="line.753"></a>
<FONT color="green">754</FONT>                            when(T, Void.class, value, observer);<a name="line.754"></a>
<FONT color="green">755</FONT>                            return null;<a name="line.755"></a>
<FONT color="green">756</FONT>                        }<a name="line.756"></a>
<FONT color="green">757</FONT>                    }<a name="line.757"></a>
<FONT color="green">758</FONT>                    enqueue.apply(new Fwd());<a name="line.758"></a>
<FONT color="green">759</FONT>                    log.sentIf(call, here + "#t" + task, here + "#p" + condition);<a name="line.759"></a>
<FONT color="green">760</FONT>                }<a name="line.760"></a>
<FONT color="green">761</FONT>            }<a name="line.761"></a>
<FONT color="green">762</FONT>        }<a name="line.762"></a>
<FONT color="green">763</FONT>    <a name="line.763"></a>
<FONT color="green">764</FONT>        private final class<a name="line.764"></a>
<FONT color="green">765</FONT>        Tail&lt;T&gt; extends Local&lt;T&gt; {<a name="line.765"></a>
<FONT color="green">766</FONT>            static private final long serialVersionUID = 1L;<a name="line.766"></a>
<FONT color="green">767</FONT>    <a name="line.767"></a>
<FONT color="green">768</FONT>            final Promise&lt;State&lt;T&gt;&gt; state;      // promise's mutable state<a name="line.768"></a>
<FONT color="green">769</FONT>    <a name="line.769"></a>
<FONT color="green">770</FONT>            Tail(final State&lt;T&gt; state) {<a name="line.770"></a>
<FONT color="green">771</FONT>                this.state = new Fulfilled&lt;State&lt;T&gt;&gt;(false, state);<a name="line.771"></a>
<FONT color="green">772</FONT>            }<a name="line.772"></a>
<FONT color="green">773</FONT>    <a name="line.773"></a>
<FONT color="green">774</FONT>            public int<a name="line.774"></a>
<FONT color="green">775</FONT>            hashCode() { return 0x3EFF7A11; }<a name="line.775"></a>
<FONT color="green">776</FONT>    <a name="line.776"></a>
<FONT color="green">777</FONT>            public boolean<a name="line.777"></a>
<FONT color="green">778</FONT>            equals(final Object x) {<a name="line.778"></a>
<FONT color="green">779</FONT>                return x instanceof Tail &amp;&amp; state.equals(((Tail&lt;?&gt;)x).state);<a name="line.779"></a>
<FONT color="green">780</FONT>            }<a name="line.780"></a>
<FONT color="green">781</FONT>    <a name="line.781"></a>
<FONT color="green">782</FONT>            public T<a name="line.782"></a>
<FONT color="green">783</FONT>            call() throws Exception {<a name="line.783"></a>
<FONT color="green">784</FONT>                final State&lt;T&gt; cell = state.call();<a name="line.784"></a>
<FONT color="green">785</FONT>                if (!cell.resolved) { throw new Unresolved(); }<a name="line.785"></a>
<FONT color="green">786</FONT>                return cell.value.call();<a name="line.786"></a>
<FONT color="green">787</FONT>            }<a name="line.787"></a>
<FONT color="green">788</FONT>    <a name="line.788"></a>
<FONT color="green">789</FONT>            public Object<a name="line.789"></a>
<FONT color="green">790</FONT>            shorten() throws Unresolved {<a name="line.790"></a>
<FONT color="green">791</FONT>                final State&lt;T&gt; cell = near(state);<a name="line.791"></a>
<FONT color="green">792</FONT>                if (!cell.resolved) { throw new Unresolved(); }<a name="line.792"></a>
<FONT color="green">793</FONT>                if (cell.value instanceof Inline) {<a name="line.793"></a>
<FONT color="green">794</FONT>                    return ((Inline&lt;?&gt;)cell.value).call();<a name="line.794"></a>
<FONT color="green">795</FONT>                }<a name="line.795"></a>
<FONT color="green">796</FONT>                return cell.value;<a name="line.796"></a>
<FONT color="green">797</FONT>            }<a name="line.797"></a>
<FONT color="green">798</FONT>    <a name="line.798"></a>
<FONT color="green">799</FONT>            public void<a name="line.799"></a>
<FONT color="green">800</FONT>            when(final Class&lt;?&gt; T, final Do&lt;? super T,?&gt; observer) {<a name="line.800"></a>
<FONT color="green">801</FONT>                near(state).observe(observer);<a name="line.801"></a>
<FONT color="green">802</FONT>            }<a name="line.802"></a>
<FONT color="green">803</FONT>        }<a name="line.803"></a>
<FONT color="green">804</FONT>    <a name="line.804"></a>
<FONT color="green">805</FONT>        private final class<a name="line.805"></a>
<FONT color="green">806</FONT>        Head&lt;T&gt; extends Struct implements Resolver&lt;T&gt;, Serializable {<a name="line.806"></a>
<FONT color="green">807</FONT>            static private final long serialVersionUID = 1L;<a name="line.807"></a>
<FONT color="green">808</FONT>    <a name="line.808"></a>
<FONT color="green">809</FONT>            private final long condition;           // id of corresponding promise<a name="line.809"></a>
<FONT color="green">810</FONT>            private final Promise&lt;State&lt;T&gt;&gt; state;  // promise's mutable state<a name="line.810"></a>
<FONT color="green">811</FONT>            private final Promise&lt;When&lt;T&gt;&gt; front;   // first when block to run<a name="line.811"></a>
<FONT color="green">812</FONT>    <a name="line.812"></a>
<FONT color="green">813</FONT>            Head(final long condition, final State&lt;T&gt; state,<a name="line.813"></a>
<FONT color="green">814</FONT>                                       final Promise&lt;When&lt;T&gt;&gt; front) {<a name="line.814"></a>
<FONT color="green">815</FONT>                this.condition = condition;<a name="line.815"></a>
<FONT color="green">816</FONT>                this.state = new Fulfilled&lt;State&lt;T&gt;&gt;(true, state);<a name="line.816"></a>
<FONT color="green">817</FONT>                this.front = front;<a name="line.817"></a>
<FONT color="green">818</FONT>    <a name="line.818"></a>
<FONT color="green">819</FONT>                /*<a name="line.819"></a>
<FONT color="green">820</FONT>                 * The resolver only holds a weak reference to the promise's mutable<a name="line.820"></a>
<FONT color="green">821</FONT>                 * state, allowing it to be garbage collected even if the resolver<a name="line.821"></a>
<FONT color="green">822</FONT>                 * is still held. This implementation takes advantage of a common<a name="line.822"></a>
<FONT color="green">823</FONT>                 * pattern in which a when block is registered on a promise as soon<a name="line.823"></a>
<FONT color="green">824</FONT>                 * as it is created, but no other reference to the promise is<a name="line.824"></a>
<FONT color="green">825</FONT>                 * retained. Combined with the recycling of when blocks, this common<a name="line.825"></a>
<FONT color="green">826</FONT>                 * pattern generates no dead objects. Much of the implementation's<a name="line.826"></a>
<FONT color="green">827</FONT>                 * complexity is in service to this goal.<a name="line.827"></a>
<FONT color="green">828</FONT>                 */<a name="line.828"></a>
<FONT color="green">829</FONT>            }<a name="line.829"></a>
<FONT color="green">830</FONT>    <a name="line.830"></a>
<FONT color="green">831</FONT>            public void<a name="line.831"></a>
<FONT color="green">832</FONT>            progress() { log.progressed(here + "#p" + condition); }<a name="line.832"></a>
<FONT color="green">833</FONT>    <a name="line.833"></a>
<FONT color="green">834</FONT>            public void<a name="line.834"></a>
<FONT color="green">835</FONT>            reject(final Exception reason) { set(null, new Rejected&lt;T&gt;(reason)); }<a name="line.835"></a>
<FONT color="green">836</FONT>    <a name="line.836"></a>
<FONT color="green">837</FONT>            public void<a name="line.837"></a>
<FONT color="green">838</FONT>            resolve(final Promise&lt;? extends T&gt; p) { set(null, p); }<a name="line.838"></a>
<FONT color="green">839</FONT>    <a name="line.839"></a>
<FONT color="green">840</FONT>            public void<a name="line.840"></a>
<FONT color="green">841</FONT>            apply(final T r) {<a name="line.841"></a>
<FONT color="green">842</FONT>                set(null==r || r instanceof Promise ? null : r.getClass(), ref(r));<a name="line.842"></a>
<FONT color="green">843</FONT>            }<a name="line.843"></a>
<FONT color="green">844</FONT>    <a name="line.844"></a>
<FONT color="green">845</FONT>            private void<a name="line.845"></a>
<FONT color="green">846</FONT>            set(final Class&lt;?&gt; T, Promise&lt;? extends T&gt; p) {<a name="line.846"></a>
<FONT color="green">847</FONT>                if (p instanceof Fulfilled) {<a name="line.847"></a>
<FONT color="green">848</FONT>                    final @SuppressWarnings("unchecked") Fulfilled&lt;? extends T&gt;<a name="line.848"></a>
<FONT color="green">849</FONT>                        fulfilled = (Fulfilled&lt;? extends T&gt;)p;<a name="line.849"></a>
<FONT color="green">850</FONT>                    p = fulfilled.getState();<a name="line.850"></a>
<FONT color="green">851</FONT>                    log.fulfilled(here + "#p" + condition);<a name="line.851"></a>
<FONT color="green">852</FONT>                } else if (p instanceof Rejected) {<a name="line.852"></a>
<FONT color="green">853</FONT>                    final @SuppressWarnings("unchecked") Rejected&lt;? extends T&gt;<a name="line.853"></a>
<FONT color="green">854</FONT>                        rejected = (Rejected&lt;? extends T&gt;)p;<a name="line.854"></a>
<FONT color="green">855</FONT>                    log.rejected(here + "#p" + condition, rejected.reason);<a name="line.855"></a>
<FONT color="green">856</FONT>                } else {<a name="line.856"></a>
<FONT color="green">857</FONT>                    log.resolved(here + "#p" + condition);<a name="line.857"></a>
<FONT color="green">858</FONT>                }<a name="line.858"></a>
<FONT color="green">859</FONT>                try {<a name="line.859"></a>
<FONT color="green">860</FONT>                    final State&lt;T&gt; cell = state.call();<a name="line.860"></a>
<FONT color="green">861</FONT>                    if (null != cell) {<a name="line.861"></a>
<FONT color="green">862</FONT>                        if (cell.resolved) { return; }<a name="line.862"></a>
<FONT color="green">863</FONT>                        cell.resolved = true;<a name="line.863"></a>
<FONT color="green">864</FONT>                        cell.T = T;<a name="line.864"></a>
<FONT color="green">865</FONT>                        cell.value = p;<a name="line.865"></a>
<FONT color="green">866</FONT>                    }<a name="line.866"></a>
<FONT color="green">867</FONT>                } catch (final Exception e) { log.problem(e); }<a name="line.867"></a>
<FONT color="green">868</FONT>                enqueue.apply(new Forward&lt;T&gt;(true, condition, front, T, p));<a name="line.868"></a>
<FONT color="green">869</FONT>            }<a name="line.869"></a>
<FONT color="green">870</FONT>        }<a name="line.870"></a>
<FONT color="green">871</FONT>    <a name="line.871"></a>
<FONT color="green">872</FONT>        /**<a name="line.872"></a>
<FONT color="green">873</FONT>         * Creates a promise in the unresolved state.<a name="line.873"></a>
<FONT color="green">874</FONT>         * &lt;p&gt;<a name="line.874"></a>
<FONT color="green">875</FONT>         * The return from this method is a ( {@linkplain Promise promise},<a name="line.875"></a>
<FONT color="green">876</FONT>         * {@linkplain Resolver resolver} ) pair. The promise is initially in the<a name="line.876"></a>
<FONT color="green">877</FONT>         * unresolved state and can only be resolved by the resolver once. If the<a name="line.877"></a>
<FONT color="green">878</FONT>         * promise is {@linkplain Resolver#apply fulfilled}, the promise will<a name="line.878"></a>
<FONT color="green">879</FONT>         * forever refer to the provided referent. If the promise, is<a name="line.879"></a>
<FONT color="green">880</FONT>         * {@linkplain Resolver#reject rejected}, the promise will forever be in the<a name="line.880"></a>
<FONT color="green">881</FONT>         * rejected state, with the provided reason. If the promise is<a name="line.881"></a>
<FONT color="green">882</FONT>         * {@linkplain Resolver#resolve resolved}, the promise will forever be in<a name="line.882"></a>
<FONT color="green">883</FONT>         * the same state as the provided promise. After this initial state<a name="line.883"></a>
<FONT color="green">884</FONT>         * transition, all subsequent invocations of either {@link Resolver#apply<a name="line.884"></a>
<FONT color="green">885</FONT>         * fulfill}, {@link Resolver#reject reject} or {@link Resolver#resolve<a name="line.885"></a>
<FONT color="green">886</FONT>         * resolve} are silently ignored. Any {@linkplain Do observer}<a name="line.886"></a>
<FONT color="green">887</FONT>         * {@linkplain #when registered} on the promise will only be notified after<a name="line.887"></a>
<FONT color="green">888</FONT>         * the promise is either fulfilled or rejected.<a name="line.888"></a>
<FONT color="green">889</FONT>         * &lt;/p&gt;<a name="line.889"></a>
<FONT color="green">890</FONT>         * @param &lt;T&gt; referent type<a name="line.890"></a>
<FONT color="green">891</FONT>         * @return ( {@linkplain Promise promise}, {@linkplain Resolver resolver} )<a name="line.891"></a>
<FONT color="green">892</FONT>         */<a name="line.892"></a>
<FONT color="green">893</FONT>        public final &lt;T&gt; Deferred&lt;T&gt;<a name="line.893"></a>
<FONT color="green">894</FONT>        defer() {<a name="line.894"></a>
<FONT color="green">895</FONT>            final long condition = near(stats).newDeferral();<a name="line.895"></a>
<FONT color="green">896</FONT>            final Promise&lt;When&lt;T&gt;&gt; front = near(stats).allocWhen(condition);<a name="line.896"></a>
<FONT color="green">897</FONT>            final State&lt;T&gt; state = new State&lt;T&gt;(condition, front);<a name="line.897"></a>
<FONT color="green">898</FONT>            return new Deferred&lt;T&gt;(new Tail&lt;T&gt;(state),<a name="line.898"></a>
<FONT color="green">899</FONT>                                   new Head&lt;T&gt;(condition, state, front));<a name="line.899"></a>
<FONT color="green">900</FONT>        }<a name="line.900"></a>
<FONT color="green">901</FONT>    <a name="line.901"></a>
<FONT color="green">902</FONT>        /**<a name="line.902"></a>
<FONT color="green">903</FONT>         * Ensures a reference is an eventual reference.<a name="line.903"></a>
<FONT color="green">904</FONT>         * &lt;p&gt;<a name="line.904"></a>
<FONT color="green">905</FONT>         * An eventual reference queues invocations, instead of processing them<a name="line.905"></a>
<FONT color="green">906</FONT>         * immediately. Each queued invocation will be processed, in order, in a<a name="line.906"></a>
<FONT color="green">907</FONT>         * future event loop turn.<a name="line.907"></a>
<FONT color="green">908</FONT>         * &lt;/p&gt;<a name="line.908"></a>
<FONT color="green">909</FONT>         * &lt;p&gt;<a name="line.909"></a>
<FONT color="green">910</FONT>         * Use this method to vet received arguments. For example:<a name="line.910"></a>
<FONT color="green">911</FONT>         * &lt;/p&gt;<a name="line.911"></a>
<FONT color="green">912</FONT>         * &lt;pre&gt;<a name="line.912"></a>
<FONT color="green">913</FONT>         * import static org.joe_e.ConstArray.array;<a name="line.913"></a>
<FONT color="green">914</FONT>         *<a name="line.914"></a>
<FONT color="green">915</FONT>         * public final class<a name="line.915"></a>
<FONT color="green">916</FONT>         * Account {<a name="line.916"></a>
<FONT color="green">917</FONT>         *<a name="line.917"></a>
<FONT color="green">918</FONT>         *     private final Eventual _;<a name="line.918"></a>
<FONT color="green">919</FONT>         *     private int balance;<a name="line.919"></a>
<FONT color="green">920</FONT>         *     private ConstArray&amp;lt;Receiver&amp;lt;Integer&amp;gt;&amp;gt; observer_s;<a name="line.920"></a>
<FONT color="green">921</FONT>         *<a name="line.921"></a>
<FONT color="green">922</FONT>         *     public<a name="line.922"></a>
<FONT color="green">923</FONT>         *     Account(final Eventual _, final int initial) {<a name="line.923"></a>
<FONT color="green">924</FONT>         *         this._ = _;<a name="line.924"></a>
<FONT color="green">925</FONT>         *         balance = initial;<a name="line.925"></a>
<FONT color="green">926</FONT>         *         observer_s = array();<a name="line.926"></a>
<FONT color="green">927</FONT>         *     }<a name="line.927"></a>
<FONT color="green">928</FONT>         *<a name="line.928"></a>
<FONT color="green">929</FONT>         *     public void<a name="line.929"></a>
<FONT color="green">930</FONT>         *     observe(final Receiver&amp;lt;Integer&amp;gt; observer) {<a name="line.930"></a>
<FONT color="green">931</FONT>         *         // Vet the received arguments.<a name="line.931"></a>
<FONT color="green">932</FONT>         *         final Receiver&amp;lt;Integer&amp;gt; observer_ = _.&lt;b&gt;_&lt;/b&gt;(observer);<a name="line.932"></a>
<FONT color="green">933</FONT>         *<a name="line.933"></a>
<FONT color="green">934</FONT>         *         // Use the &lt;em&gt;vetted&lt;/em&gt; arguments.<a name="line.934"></a>
<FONT color="green">935</FONT>         *         observer_s = observer_s.with(observer_);<a name="line.935"></a>
<FONT color="green">936</FONT>         *     }<a name="line.936"></a>
<FONT color="green">937</FONT>         *<a name="line.937"></a>
<FONT color="green">938</FONT>         *     public int<a name="line.938"></a>
<FONT color="green">939</FONT>         *     getBalance() { return balance; }<a name="line.939"></a>
<FONT color="green">940</FONT>         *<a name="line.940"></a>
<FONT color="green">941</FONT>         *     public void<a name="line.941"></a>
<FONT color="green">942</FONT>         *     setBalance(final int newBalance) {<a name="line.942"></a>
<FONT color="green">943</FONT>         *          balance = newBalance;<a name="line.943"></a>
<FONT color="green">944</FONT>         *          for (final Receiver&amp;lt;Integer&amp;gt; observer_ : observer_s) {<a name="line.944"></a>
<FONT color="green">945</FONT>         *              // Schedule future execution of notification.<a name="line.945"></a>
<FONT color="green">946</FONT>         *              observer_.apply(newBalance);<a name="line.946"></a>
<FONT color="green">947</FONT>         *          }<a name="line.947"></a>
<FONT color="green">948</FONT>         *     }<a name="line.948"></a>
<FONT color="green">949</FONT>         * }<a name="line.949"></a>
<FONT color="green">950</FONT>         * &lt;/pre&gt;<a name="line.950"></a>
<FONT color="green">951</FONT>         * &lt;p&gt;<a name="line.951"></a>
<FONT color="green">952</FONT>         * By convention, the return from this method is held in a variable whose<a name="line.952"></a>
<FONT color="green">953</FONT>         * name is suffixed with an '{@code _}' character. The main part of the<a name="line.953"></a>
<FONT color="green">954</FONT>         * variable name should use Java's camelCaseConvention. A list of eventual<a name="line.954"></a>
<FONT color="green">955</FONT>         * references is suffixed with "{@code _s}". This naming convention<a name="line.955"></a>
<FONT color="green">956</FONT>         * creates the appearance of a new operator in the Java language, the<a name="line.956"></a>
<FONT color="green">957</FONT>         * eventual operator: "&lt;b&gt;{@code _.}&lt;/b&gt;".<a name="line.957"></a>
<FONT color="green">958</FONT>         * &lt;/p&gt;<a name="line.958"></a>
<FONT color="green">959</FONT>         * &lt;p&gt;<a name="line.959"></a>
<FONT color="green">960</FONT>         * If this method returns successfully, the returned eventual reference<a name="line.960"></a>
<FONT color="green">961</FONT>         * will not throw an {@link Exception} on invocation of any of the methods<a name="line.961"></a>
<FONT color="green">962</FONT>         * defined by its type, provided the invoked method's return type is either<a name="line.962"></a>
<FONT color="green">963</FONT>         * {@code void}, an {@linkplain Proxies#isImplementable allowed} proxy<a name="line.963"></a>
<FONT color="green">964</FONT>         * type or assignable from {@link Promise}. Invocations on the eventual<a name="line.964"></a>
<FONT color="green">965</FONT>         * reference will not give the {@code referent}, nor any of the invocation<a name="line.965"></a>
<FONT color="green">966</FONT>         * arguments, an opportunity to execute in the current event loop turn.<a name="line.966"></a>
<FONT color="green">967</FONT>         * &lt;/p&gt;<a name="line.967"></a>
<FONT color="green">968</FONT>         * &lt;p&gt;<a name="line.968"></a>
<FONT color="green">969</FONT>         * Invocations of methods defined by {@link Object} are &lt;strong&gt;not&lt;/strong&gt;<a name="line.969"></a>
<FONT color="green">970</FONT>         * queued, and so can cause plan interference, or throw an exception.<a name="line.970"></a>
<FONT color="green">971</FONT>         * &lt;/p&gt;<a name="line.971"></a>
<FONT color="green">972</FONT>         * @param &lt;T&gt; referent type, MUST be an<a name="line.972"></a>
<FONT color="green">973</FONT>         *            {@linkplain Proxies#isImplementable allowed} proxy type<a name="line.973"></a>
<FONT color="green">974</FONT>         * @param referent  immediate or eventual reference,<a name="line.974"></a>
<FONT color="green">975</FONT>         *                  MUST be non-{@code null}<a name="line.975"></a>
<FONT color="green">976</FONT>         * @return corresponding eventual reference<a name="line.976"></a>
<FONT color="green">977</FONT>         * @throws NullPointerException {@code null} {@code referent}<a name="line.977"></a>
<FONT color="green">978</FONT>         * @throws ClassCastException   {@code T} not an<a name="line.978"></a>
<FONT color="green">979</FONT>         *                  {@linkplain Proxies#isImplementable allowed} proxy type<a name="line.979"></a>
<FONT color="green">980</FONT>         */<a name="line.980"></a>
<FONT color="green">981</FONT>        public final &lt;T&gt; T<a name="line.981"></a>
<FONT color="green">982</FONT>        _(final T referent) {<a name="line.982"></a>
<FONT color="green">983</FONT>            if (referent instanceof Proxy) {<a name="line.983"></a>
<FONT color="green">984</FONT>                final Object handler = Proxies.getHandler((Proxy)referent);<a name="line.984"></a>
<FONT color="green">985</FONT>                if ((null != handler &amp;&amp; Rejected.class == handler.getClass()) ||<a name="line.985"></a>
<FONT color="green">986</FONT>                    trusted(handler)) { return referent; }<a name="line.986"></a>
<FONT color="green">987</FONT>            }<a name="line.987"></a>
<FONT color="green">988</FONT>            final @SuppressWarnings("unchecked") T proxy =<a name="line.988"></a>
<FONT color="green">989</FONT>                (T)Proxies.proxy(new Enqueue&lt;T&gt;(ref(referent)),<a name="line.989"></a>
<FONT color="green">990</FONT>                                 virtualize(referent.getClass(), Selfless.class));<a name="line.990"></a>
<FONT color="green">991</FONT>            return proxy;<a name="line.991"></a>
<FONT color="green">992</FONT>        }<a name="line.992"></a>
<FONT color="green">993</FONT>    <a name="line.993"></a>
<FONT color="green">994</FONT>        /**<a name="line.994"></a>
<FONT color="green">995</FONT>         * Lists the part of an interface that a proxy can implement.<a name="line.995"></a>
<FONT color="green">996</FONT>         * @param r types to mimic<a name="line.996"></a>
<FONT color="green">997</FONT>         */<a name="line.997"></a>
<FONT color="green">998</FONT>        static protected Class&lt;?&gt;[]<a name="line.998"></a>
<FONT color="green">999</FONT>        virtualize(Class&lt;?&gt;... r) {<a name="line.999"></a>
<FONT color="green">1000</FONT>            for (int i = r.length; i-- != 0;) {<a name="line.1000"></a>
<FONT color="green">1001</FONT>                final Class&lt;?&gt; type = r[i];<a name="line.1001"></a>
<FONT color="green">1002</FONT>                if (type == Serializable.class || !Proxies.isImplementable(type) ||<a name="line.1002"></a>
<FONT color="green">1003</FONT>                        JoeE.isSubtypeOf(type, Immutable.class) ||<a name="line.1003"></a>
<FONT color="green">1004</FONT>                        JoeE.isSubtypeOf(type, Equatable.class)) {<a name="line.1004"></a>
<FONT color="green">1005</FONT>                    // remove the type from the proxy type list<a name="line.1005"></a>
<FONT color="green">1006</FONT>                    {<a name="line.1006"></a>
<FONT color="green">1007</FONT>                        final Class&lt;?&gt;[] c = r;<a name="line.1007"></a>
<FONT color="green">1008</FONT>                        r = new Class&lt;?&gt;[c.length - 1];<a name="line.1008"></a>
<FONT color="green">1009</FONT>                        System.arraycopy(c, 0, r, 0, i);<a name="line.1009"></a>
<FONT color="green">1010</FONT>                        System.arraycopy(c, i + 1, r, i, r.length - i);<a name="line.1010"></a>
<FONT color="green">1011</FONT>                    }<a name="line.1011"></a>
<FONT color="green">1012</FONT>    <a name="line.1012"></a>
<FONT color="green">1013</FONT>                    // search the inheritance tree for types that can be implemented<a name="line.1013"></a>
<FONT color="green">1014</FONT>                    for (Class&lt;?&gt; p = type; null != p; p = p.getSuperclass()) {<a name="line.1014"></a>
<FONT color="green">1015</FONT>                        Class&lt;?&gt;[] x = virtualize(p.getInterfaces());<a name="line.1015"></a>
<FONT color="green">1016</FONT>    <a name="line.1016"></a>
<FONT color="green">1017</FONT>                        // remove any duplicate types from the replacement type list<a name="line.1017"></a>
<FONT color="green">1018</FONT>                        for (int j = x.length; 0 != j--;) {<a name="line.1018"></a>
<FONT color="green">1019</FONT>                            for (int k = r.length; 0 != k--;) {<a name="line.1019"></a>
<FONT color="green">1020</FONT>                                if (x[j] == r[k]) {<a name="line.1020"></a>
<FONT color="green">1021</FONT>                                    final Class&lt;?&gt;[] c = x;<a name="line.1021"></a>
<FONT color="green">1022</FONT>                                    x = new Class&lt;?&gt;[c.length - 1];<a name="line.1022"></a>
<FONT color="green">1023</FONT>                                    System.arraycopy(c, 0, x, 0, j);<a name="line.1023"></a>
<FONT color="green">1024</FONT>                                    System.arraycopy(c, j + 1, x, j, x.length - j);<a name="line.1024"></a>
<FONT color="green">1025</FONT>                                    break;<a name="line.1025"></a>
<FONT color="green">1026</FONT>                                }<a name="line.1026"></a>
<FONT color="green">1027</FONT>                            }<a name="line.1027"></a>
<FONT color="green">1028</FONT>                        }<a name="line.1028"></a>
<FONT color="green">1029</FONT>    <a name="line.1029"></a>
<FONT color="green">1030</FONT>                        // splice in the replacement type list<a name="line.1030"></a>
<FONT color="green">1031</FONT>                        final Class&lt;?&gt;[] c = r;<a name="line.1031"></a>
<FONT color="green">1032</FONT>                        r = new Class&lt;?&gt;[c.length + x.length];<a name="line.1032"></a>
<FONT color="green">1033</FONT>                        System.arraycopy(c, 0, r, 0, i);<a name="line.1033"></a>
<FONT color="green">1034</FONT>                        System.arraycopy(x, 0, r, i, x.length);<a name="line.1034"></a>
<FONT color="green">1035</FONT>                        System.arraycopy(c, i, r, i + x.length, c.length - i);<a name="line.1035"></a>
<FONT color="green">1036</FONT>                    }<a name="line.1036"></a>
<FONT color="green">1037</FONT>                }<a name="line.1037"></a>
<FONT color="green">1038</FONT>            }<a name="line.1038"></a>
<FONT color="green">1039</FONT>            return r;<a name="line.1039"></a>
<FONT color="green">1040</FONT>        }<a name="line.1040"></a>
<FONT color="green">1041</FONT>    <a name="line.1041"></a>
<FONT color="green">1042</FONT>        /**<a name="line.1042"></a>
<FONT color="green">1043</FONT>         * Causes a compile error for code that attempts to create an<a name="line.1043"></a>
<FONT color="green">1044</FONT>         * {@linkplain #_ eventual reference} of a concrete type.<a name="line.1044"></a>
<FONT color="green">1045</FONT>         * &lt;p&gt;<a name="line.1045"></a>
<FONT color="green">1046</FONT>         * If you encounter a compile error because your code is linking to this<a name="line.1046"></a>
<FONT color="green">1047</FONT>         * method, insert an explicit cast to the<a name="line.1047"></a>
<FONT color="green">1048</FONT>         * {@linkplain Proxies#isImplementable allowed} proxy type. For example,<a name="line.1048"></a>
<FONT color="green">1049</FONT>         * &lt;/p&gt;<a name="line.1049"></a>
<FONT color="green">1050</FONT>         * &lt;kbd&gt;_._(this).apply(null);&lt;/kbd&gt;<a name="line.1050"></a>
<FONT color="green">1051</FONT>         * &lt;p&gt;becomes:&lt;/p&gt;<a name="line.1051"></a>
<FONT color="green">1052</FONT>         * &lt;kbd&gt;_._((Receiver&amp;lt;?&amp;gt;)this).apply(null);&lt;/kbd&gt;<a name="line.1052"></a>
<FONT color="green">1053</FONT>         * @param x ignored<a name="line.1053"></a>
<FONT color="green">1054</FONT>         * @throws AssertionError   always thrown<a name="line.1054"></a>
<FONT color="green">1055</FONT>         */<a name="line.1055"></a>
<FONT color="green">1056</FONT>        public final &lt;T extends Serializable&gt; void<a name="line.1056"></a>
<FONT color="green">1057</FONT>        _(final T x) { throw new AssertionError(); }<a name="line.1057"></a>
<FONT color="green">1058</FONT>    <a name="line.1058"></a>
<FONT color="green">1059</FONT>        /**<a name="line.1059"></a>
<FONT color="green">1060</FONT>         * Casts a promise to a specified type.<a name="line.1060"></a>
<FONT color="green">1061</FONT>         * &lt;p&gt;<a name="line.1061"></a>
<FONT color="green">1062</FONT>         * For example,<a name="line.1062"></a>
<FONT color="green">1063</FONT>         * &lt;/p&gt;<a name="line.1063"></a>
<FONT color="green">1064</FONT>         * &lt;pre&gt;<a name="line.1064"></a>
<FONT color="green">1065</FONT>         *  final Channel&amp;lt;Receiver&amp;lt;Integer&amp;gt;&amp;gt; x = _.defer();<a name="line.1065"></a>
<FONT color="green">1066</FONT>         *  final Receiver&amp;lt;Integer&amp;gt; r_ = cast(Receiver.class, x.promise);<a name="line.1066"></a>
<FONT color="green">1067</FONT>         * &lt;/pre&gt;<a name="line.1067"></a>
<FONT color="green">1068</FONT>         * @param &lt;T&gt; referent type to implement<a name="line.1068"></a>
<FONT color="green">1069</FONT>         * @param type      referent type to implement<a name="line.1069"></a>
<FONT color="green">1070</FONT>         * @param promise   promise for the referent<a name="line.1070"></a>
<FONT color="green">1071</FONT>         * @return reference of corresponding type<a name="line.1071"></a>
<FONT color="green">1072</FONT>         * @throws ClassCastException   no cast to {@code type}<a name="line.1072"></a>
<FONT color="green">1073</FONT>         */<a name="line.1073"></a>
<FONT color="green">1074</FONT>        static public @SuppressWarnings("unchecked") &lt;T&gt; T<a name="line.1074"></a>
<FONT color="green">1075</FONT>        cast(final Class&lt;?&gt; type,final Promise&lt;T&gt; promise)throws ClassCastException{<a name="line.1075"></a>
<FONT color="green">1076</FONT>            return (T)(Void.class == type || void.class == type ?<a name="line.1076"></a>
<FONT color="green">1077</FONT>                    null :<a name="line.1077"></a>
<FONT color="green">1078</FONT>                Promise.class == type ?<a name="line.1078"></a>
<FONT color="green">1079</FONT>                    promise :<a name="line.1079"></a>
<FONT color="green">1080</FONT>                promise instanceof Fulfilled ?<a name="line.1080"></a>
<FONT color="green">1081</FONT>                    near(promise) :<a name="line.1081"></a>
<FONT color="green">1082</FONT>                type.isInstance(promise) ?<a name="line.1082"></a>
<FONT color="green">1083</FONT>                    promise :<a name="line.1083"></a>
<FONT color="green">1084</FONT>                float.class == type ?<a name="line.1084"></a>
<FONT color="green">1085</FONT>                    Float.NaN :<a name="line.1085"></a>
<FONT color="green">1086</FONT>                double.class == type ?<a name="line.1086"></a>
<FONT color="green">1087</FONT>                    Double.NaN :<a name="line.1087"></a>
<FONT color="green">1088</FONT>                null == promise ?<a name="line.1088"></a>
<FONT color="green">1089</FONT>                    null :<a name="line.1089"></a>
<FONT color="green">1090</FONT>                Float.class == type ?<a name="line.1090"></a>
<FONT color="green">1091</FONT>                    Float.NaN :<a name="line.1091"></a>
<FONT color="green">1092</FONT>                Double.class == type ?<a name="line.1092"></a>
<FONT color="green">1093</FONT>                    Double.NaN :<a name="line.1093"></a>
<FONT color="green">1094</FONT>                Selfless.class == type ?<a name="line.1094"></a>
<FONT color="green">1095</FONT>                    Proxies.proxy((InvocationHandler)promise, Selfless.class) :<a name="line.1095"></a>
<FONT color="green">1096</FONT>                Proxies.proxy((InvocationHandler)promise, type, Selfless.class));<a name="line.1096"></a>
<FONT color="green">1097</FONT>        }<a name="line.1097"></a>
<FONT color="green">1098</FONT>    <a name="line.1098"></a>
<FONT color="green">1099</FONT>        /**<a name="line.1099"></a>
<FONT color="green">1100</FONT>         * Gets a corresponding {@linkplain Promise promise}.<a name="line.1100"></a>
<FONT color="green">1101</FONT>         * &lt;p&gt;<a name="line.1101"></a>
<FONT color="green">1102</FONT>         * This method is the inverse of {@link #cast cast}; it gets the<a name="line.1102"></a>
<FONT color="green">1103</FONT>         * corresponding {@linkplain Promise promise} for a given reference.<a name="line.1103"></a>
<FONT color="green">1104</FONT>         * &lt;/p&gt;<a name="line.1104"></a>
<FONT color="green">1105</FONT>         * &lt;p&gt;<a name="line.1105"></a>
<FONT color="green">1106</FONT>         * This method will not throw an {@link Exception}.<a name="line.1106"></a>
<FONT color="green">1107</FONT>         * &lt;/p&gt;<a name="line.1107"></a>
<FONT color="green">1108</FONT>         * @param &lt;T&gt; referent type<a name="line.1108"></a>
<FONT color="green">1109</FONT>         * @param referent immediate or eventual reference<a name="line.1109"></a>
<FONT color="green">1110</FONT>         */<a name="line.1110"></a>
<FONT color="green">1111</FONT>        static public @SuppressWarnings("unchecked") &lt;T&gt; Promise&lt;T&gt;<a name="line.1111"></a>
<FONT color="green">1112</FONT>        ref(final T referent) {<a name="line.1112"></a>
<FONT color="green">1113</FONT>            if (null == referent) { return null; }<a name="line.1113"></a>
<FONT color="green">1114</FONT>            if (referent instanceof Promise) { return (Promise&lt;T&gt;)referent; }<a name="line.1114"></a>
<FONT color="green">1115</FONT>            if (referent instanceof Proxy) {<a name="line.1115"></a>
<FONT color="green">1116</FONT>                try {<a name="line.1116"></a>
<FONT color="green">1117</FONT>                    final Object handler = Proxies.getHandler((Proxy)referent);<a name="line.1117"></a>
<FONT color="green">1118</FONT>                    if (handler instanceof Promise) {<a name="line.1118"></a>
<FONT color="green">1119</FONT>                        return handler instanceof Enqueue<a name="line.1119"></a>
<FONT color="green">1120</FONT>                            ? ((Enqueue&lt;T&gt;)handler).untrusted : (Promise&lt;T&gt;)handler;<a name="line.1120"></a>
<FONT color="green">1121</FONT>                    }<a name="line.1121"></a>
<FONT color="green">1122</FONT>                } catch (final Exception e) { /* treat as normal reference */ }<a name="line.1122"></a>
<FONT color="green">1123</FONT>            }<a name="line.1123"></a>
<FONT color="green">1124</FONT>            try {<a name="line.1124"></a>
<FONT color="green">1125</FONT>                if (referent instanceof Double) {<a name="line.1125"></a>
<FONT color="green">1126</FONT>                    final Double d = (Double)referent;<a name="line.1126"></a>
<FONT color="green">1127</FONT>                    if (d.isNaN())      { throw new ArithmeticException(); }<a name="line.1127"></a>
<FONT color="green">1128</FONT>                    if (d.isInfinite()) { throw new ArithmeticException(); }<a name="line.1128"></a>
<FONT color="green">1129</FONT>                } else if (referent instanceof Float) {<a name="line.1129"></a>
<FONT color="green">1130</FONT>                    final Float f = (Float)referent;<a name="line.1130"></a>
<FONT color="green">1131</FONT>                    if (f.isNaN())      { throw new ArithmeticException(); }<a name="line.1131"></a>
<FONT color="green">1132</FONT>                    if (f.isInfinite()) { throw new ArithmeticException(); }<a name="line.1132"></a>
<FONT color="green">1133</FONT>                }<a name="line.1133"></a>
<FONT color="green">1134</FONT>                return new Fulfilled&lt;T&gt;(false, referent);<a name="line.1134"></a>
<FONT color="green">1135</FONT>            } catch (final Exception e) {<a name="line.1135"></a>
<FONT color="green">1136</FONT>                return reject(e);<a name="line.1136"></a>
<FONT color="green">1137</FONT>            }<a name="line.1137"></a>
<FONT color="green">1138</FONT>        }<a name="line.1138"></a>
<FONT color="green">1139</FONT>    <a name="line.1139"></a>
<FONT color="green">1140</FONT>        /**<a name="line.1140"></a>
<FONT color="green">1141</FONT>         * Gets a corresponding immediate reference.<a name="line.1141"></a>
<FONT color="green">1142</FONT>         * &lt;p&gt;<a name="line.1142"></a>
<FONT color="green">1143</FONT>         * This method should only be used when the application knows the provided<a name="line.1143"></a>
<FONT color="green">1144</FONT>         * reference refers to a local object. Any other condition is treated as a<a name="line.1144"></a>
<FONT color="green">1145</FONT>         * fatal error. Use the {@link Promise#call call} method to check the status<a name="line.1145"></a>
<FONT color="green">1146</FONT>         * of a promise.<a name="line.1146"></a>
<FONT color="green">1147</FONT>         * &lt;/p&gt;<a name="line.1147"></a>
<FONT color="green">1148</FONT>         * &lt;p&gt;<a name="line.1148"></a>
<FONT color="green">1149</FONT>         * This method will not throw an {@link Exception}.<a name="line.1149"></a>
<FONT color="green">1150</FONT>         * &lt;/p&gt;<a name="line.1150"></a>
<FONT color="green">1151</FONT>         * @param &lt;T&gt; referent type<a name="line.1151"></a>
<FONT color="green">1152</FONT>         * @param reference possibly eventual reference for a local referent<a name="line.1152"></a>
<FONT color="green">1153</FONT>         * @return corresponding immediate reference<a name="line.1153"></a>
<FONT color="green">1154</FONT>         */<a name="line.1154"></a>
<FONT color="green">1155</FONT>        static public &lt;T&gt; T<a name="line.1155"></a>
<FONT color="green">1156</FONT>        near(final T reference) { return near(ref(reference)); }<a name="line.1156"></a>
<FONT color="green">1157</FONT>    <a name="line.1157"></a>
<FONT color="green">1158</FONT>        /**<a name="line.1158"></a>
<FONT color="green">1159</FONT>         * Gets a corresponding immediate reference.<a name="line.1159"></a>
<FONT color="green">1160</FONT>         * &lt;p&gt;<a name="line.1160"></a>
<FONT color="green">1161</FONT>         * This method should only be used when the application knows the provided<a name="line.1161"></a>
<FONT color="green">1162</FONT>         * promise refers to a local object. Any other condition is treated as a<a name="line.1162"></a>
<FONT color="green">1163</FONT>         * fatal error. Use the {@link Promise#call call} method to check the status<a name="line.1163"></a>
<FONT color="green">1164</FONT>         * of a promise.<a name="line.1164"></a>
<FONT color="green">1165</FONT>         * &lt;/p&gt;<a name="line.1165"></a>
<FONT color="green">1166</FONT>         * &lt;p&gt;<a name="line.1166"></a>
<FONT color="green">1167</FONT>         * This method will not throw an {@link Exception}.<a name="line.1167"></a>
<FONT color="green">1168</FONT>         * &lt;/p&gt;<a name="line.1168"></a>
<FONT color="green">1169</FONT>         * @param &lt;T&gt; referent type<a name="line.1169"></a>
<FONT color="green">1170</FONT>         * @param promise   a promise<a name="line.1170"></a>
<FONT color="green">1171</FONT>         * @return {@linkplain #cast corresponding} reference<a name="line.1171"></a>
<FONT color="green">1172</FONT>         */<a name="line.1172"></a>
<FONT color="green">1173</FONT>        static public &lt;T&gt; T<a name="line.1173"></a>
<FONT color="green">1174</FONT>        near(final Promise&lt;T&gt; promise) {<a name="line.1174"></a>
<FONT color="green">1175</FONT>            try {<a name="line.1175"></a>
<FONT color="green">1176</FONT>                return promise.call();<a name="line.1176"></a>
<FONT color="green">1177</FONT>            } catch (final Exception e) { throw new Error(e); }<a name="line.1177"></a>
<FONT color="green">1178</FONT>        }<a name="line.1178"></a>
<FONT color="green">1179</FONT>    <a name="line.1179"></a>
<FONT color="green">1180</FONT>        /**<a name="line.1180"></a>
<FONT color="green">1181</FONT>         * Constructs a rejected {@linkplain Promise promise}.<a name="line.1181"></a>
<FONT color="green">1182</FONT>         * @param &lt;T&gt; referent type<a name="line.1182"></a>
<FONT color="green">1183</FONT>         * @param reason    rejection reason<a name="line.1183"></a>
<FONT color="green">1184</FONT>         */<a name="line.1184"></a>
<FONT color="green">1185</FONT>        static public &lt;T&gt; Promise&lt;T&gt;<a name="line.1185"></a>
<FONT color="green">1186</FONT>        reject(final Exception reason) { return new Rejected&lt;T&gt;(reason); }<a name="line.1186"></a>
<FONT color="green">1187</FONT>    <a name="line.1187"></a>
<FONT color="green">1188</FONT>        /**<a name="line.1188"></a>
<FONT color="green">1189</FONT>         * Creates a sub-vat.<a name="line.1189"></a>
<FONT color="green">1190</FONT>         * &lt;p&gt;<a name="line.1190"></a>
<FONT color="green">1191</FONT>         * All created vats will be destructed when this vat is<a name="line.1191"></a>
<FONT color="green">1192</FONT>         * {@linkplain Vat#destruct destructed}.<a name="line.1192"></a>
<FONT color="green">1193</FONT>         * &lt;/p&gt;<a name="line.1193"></a>
<FONT color="green">1194</FONT>         * &lt;p&gt;<a name="line.1194"></a>
<FONT color="green">1195</FONT>         * The {@code maker} MUST be a {@code public}<a name="line.1195"></a>
<FONT color="green">1196</FONT>         * {@linkplain org.joe_e.IsJoeE Joe-E} class with a method of signature:<a name="line.1196"></a>
<FONT color="green">1197</FONT>         * &lt;/p&gt;<a name="line.1197"></a>
<FONT color="green">1198</FONT>         * &lt;pre&gt;<a name="line.1198"></a>
<FONT color="green">1199</FONT>         * static public R<a name="line.1199"></a>
<FONT color="green">1200</FONT>         * make({@link Eventual} _, &amp;hellip;)<a name="line.1200"></a>
<FONT color="green">1201</FONT>         * &lt;/pre&gt;<a name="line.1201"></a>
<FONT color="green">1202</FONT>         * &lt;p&gt;<a name="line.1202"></a>
<FONT color="green">1203</FONT>         * The ellipsis means the method can have any number of additional<a name="line.1203"></a>
<FONT color="green">1204</FONT>         * arguments. The {@link Eventual} parameter, if present, MUST be the first<a name="line.1204"></a>
<FONT color="green">1205</FONT>         * parameter.<a name="line.1205"></a>
<FONT color="green">1206</FONT>         * &lt;/p&gt;<a name="line.1206"></a>
<FONT color="green">1207</FONT>         * &lt;p&gt;<a name="line.1207"></a>
<FONT color="green">1208</FONT>         * This method will not throw an {@link Exception}. None of the arguments<a name="line.1208"></a>
<FONT color="green">1209</FONT>         * will be given the opportunity to execute in the current event loop turn.<a name="line.1209"></a>
<FONT color="green">1210</FONT>         * &lt;/p&gt;<a name="line.1210"></a>
<FONT color="green">1211</FONT>         * @param &lt;R&gt; return type, MUST be either an interface, or a {@link Promise}<a name="line.1211"></a>
<FONT color="green">1212</FONT>         * @param label     optional vat label,<a name="line.1212"></a>
<FONT color="green">1213</FONT>         *                  if {@code null} a label will be generated<a name="line.1213"></a>
<FONT color="green">1214</FONT>         * @param maker     constructor class<a name="line.1214"></a>
<FONT color="green">1215</FONT>         * @param optional  more arguments for {@code maker}'s make method<a name="line.1215"></a>
<FONT color="green">1216</FONT>         * @return sub-vat permissions, including a promise for the object returned<a name="line.1216"></a>
<FONT color="green">1217</FONT>         *         by the {@code maker}<a name="line.1217"></a>
<FONT color="green">1218</FONT>         */<a name="line.1218"></a>
<FONT color="green">1219</FONT>        public &lt;R&gt; Vat&lt;R&gt;<a name="line.1219"></a>
<FONT color="green">1220</FONT>        spawn(final String label, final Class&lt;?&gt; maker, final Object... optional) {<a name="line.1220"></a>
<FONT color="green">1221</FONT>            /**<a name="line.1221"></a>
<FONT color="green">1222</FONT>             * The default implementation just calls the make method in a separate<a name="line.1222"></a>
<FONT color="green">1223</FONT>             * event loop turn.<a name="line.1223"></a>
<FONT color="green">1224</FONT>             */<a name="line.1224"></a>
<FONT color="green">1225</FONT>            try {<a name="line.1225"></a>
<FONT color="green">1226</FONT>                final Method make = NotAMaker.dispatch(maker);<a name="line.1226"></a>
<FONT color="green">1227</FONT>                final Class&lt;?&gt;[] paramv = make.getParameterTypes();<a name="line.1227"></a>
<FONT color="green">1228</FONT>                final ConstArray.Builder&lt;Object&gt; argv =<a name="line.1228"></a>
<FONT color="green">1229</FONT>                    ConstArray.builder(paramv.length);<a name="line.1229"></a>
<FONT color="green">1230</FONT>                if (0 != paramv.length &amp;&amp; Eventual.class == paramv[0]) {<a name="line.1230"></a>
<FONT color="green">1231</FONT>                    argv.append(this);<a name="line.1231"></a>
<FONT color="green">1232</FONT>                }<a name="line.1232"></a>
<FONT color="green">1233</FONT>                for (final Object x : optional) { argv.append(x); }<a name="line.1233"></a>
<FONT color="green">1234</FONT>                final @SuppressWarnings("unchecked") R top =<a name="line.1234"></a>
<FONT color="green">1235</FONT>                    (R)when(maker, new Invoke&lt;Class&lt;?&gt;&gt;(make, argv.snapshot()));<a name="line.1235"></a>
<FONT color="green">1236</FONT>                final Promise&lt;Receiver&lt;?&gt;&gt; ignore = reject(null);<a name="line.1236"></a>
<FONT color="green">1237</FONT>                return new Vat&lt;R&gt;(top, cast(Receiver.class, ignore));<a name="line.1237"></a>
<FONT color="green">1238</FONT>            } catch (final Exception e) { throw new Error(e); }<a name="line.1238"></a>
<FONT color="green">1239</FONT>        }<a name="line.1239"></a>
<FONT color="green">1240</FONT>    <a name="line.1240"></a>
<FONT color="green">1241</FONT>    //  The following convenience overloads are supported under JDK1.6 and early<a name="line.1241"></a>
<FONT color="green">1242</FONT>    //  versions of JDK1.5, but not on later versions of JDK1.5. They support a<a name="line.1242"></a>
<FONT color="green">1243</FONT>    //  slighter better syntax and are faster than the generic implementations.<a name="line.1243"></a>
<FONT color="green">1244</FONT>    //<a name="line.1244"></a>
<FONT color="green">1245</FONT>    //  /**<a name="line.1245"></a>
<FONT color="green">1246</FONT>    //   * Registers an observer on a promise.<a name="line.1246"></a>
<FONT color="green">1247</FONT>    //   * &lt;p&gt;<a name="line.1247"></a>
<FONT color="green">1248</FONT>    //   * The implementation behavior is the same as that documented for the<a name="line.1248"></a>
<FONT color="green">1249</FONT>    //   * promise based {@link #when(Promise, Do) when} statement.<a name="line.1249"></a>
<FONT color="green">1250</FONT>    //   * &lt;/p&gt;<a name="line.1250"></a>
<FONT color="green">1251</FONT>    //   * @param &lt;P&gt; {@code observer}'s parameter type<a name="line.1251"></a>
<FONT color="green">1252</FONT>    //   * @param &lt;R&gt; {@code observer}'s return type<a name="line.1252"></a>
<FONT color="green">1253</FONT>    //   * @param promise   observed promise<a name="line.1253"></a>
<FONT color="green">1254</FONT>    //   * @param observer  observer, MUST NOT be {@code null}<a name="line.1254"></a>
<FONT color="green">1255</FONT>    //   * @return promise for the observer's return value<a name="line.1255"></a>
<FONT color="green">1256</FONT>    //   */<a name="line.1256"></a>
<FONT color="green">1257</FONT>    //  public final &lt;P,R extends Serializable&gt; Promise&lt;R&gt;<a name="line.1257"></a>
<FONT color="green">1258</FONT>    //  when(final Promise&lt;P&gt; promise, final Do&lt;P,R&gt; observer) {<a name="line.1258"></a>
<FONT color="green">1259</FONT>    //      try {<a name="line.1259"></a>
<FONT color="green">1260</FONT>    //          return when(Object.class, promise, observer);<a name="line.1260"></a>
<FONT color="green">1261</FONT>    //      } catch (final Exception e) { throw new Error(e); }<a name="line.1261"></a>
<FONT color="green">1262</FONT>    //  }<a name="line.1262"></a>
<FONT color="green">1263</FONT>    //<a name="line.1263"></a>
<FONT color="green">1264</FONT>    //  /**<a name="line.1264"></a>
<FONT color="green">1265</FONT>    //   * Registers an observer on a promise.<a name="line.1265"></a>
<FONT color="green">1266</FONT>    //   * &lt;p&gt;<a name="line.1266"></a>
<FONT color="green">1267</FONT>    //   * The implementation behavior is the same as that documented for the<a name="line.1267"></a>
<FONT color="green">1268</FONT>    //   * promise based {@link #when(Promise, Do) when} statement.<a name="line.1268"></a>
<FONT color="green">1269</FONT>    //   * &lt;/p&gt;<a name="line.1269"></a>
<FONT color="green">1270</FONT>    //   * @param &lt;P&gt; {@code observer}'s parameter type<a name="line.1270"></a>
<FONT color="green">1271</FONT>    //   * @param promise   observed promise<a name="line.1271"></a>
<FONT color="green">1272</FONT>    //   * @param observer  observer, MUST NOT be {@code null}<a name="line.1272"></a>
<FONT color="green">1273</FONT>    //   */<a name="line.1273"></a>
<FONT color="green">1274</FONT>    //  public final &lt;P&gt; void<a name="line.1274"></a>
<FONT color="green">1275</FONT>    //  when(final Promise&lt;P&gt; promise, final Do&lt;P,Void&gt; observer) {<a name="line.1275"></a>
<FONT color="green">1276</FONT>    //      try {<a name="line.1276"></a>
<FONT color="green">1277</FONT>    //          when(Void.class, promise, observer);<a name="line.1277"></a>
<FONT color="green">1278</FONT>    //      } catch (final Exception e) { throw new Error(e); }<a name="line.1278"></a>
<FONT color="green">1279</FONT>    //  }<a name="line.1279"></a>
<FONT color="green">1280</FONT>    //<a name="line.1280"></a>
<FONT color="green">1281</FONT>    //  /**<a name="line.1281"></a>
<FONT color="green">1282</FONT>    //   * Registers an observer on an {@linkplain #_ eventual reference}.<a name="line.1282"></a>
<FONT color="green">1283</FONT>    //   * &lt;p&gt;<a name="line.1283"></a>
<FONT color="green">1284</FONT>    //   * The implementation behavior is the same as that documented for the<a name="line.1284"></a>
<FONT color="green">1285</FONT>    //   * promise based {@link #when(Promise, Do) when} statement.<a name="line.1285"></a>
<FONT color="green">1286</FONT>    //   * &lt;/p&gt;<a name="line.1286"></a>
<FONT color="green">1287</FONT>    //   * @param &lt;P&gt; {@code observer}'s parameter type<a name="line.1287"></a>
<FONT color="green">1288</FONT>    //   * @param &lt;R&gt; {@code observer}'s return type<a name="line.1288"></a>
<FONT color="green">1289</FONT>    //   * @param reference observed reference<a name="line.1289"></a>
<FONT color="green">1290</FONT>    //   * @param observer  observer, MUST NOT be {@code null}<a name="line.1290"></a>
<FONT color="green">1291</FONT>    //   * @return promise for the observer's return value<a name="line.1291"></a>
<FONT color="green">1292</FONT>    //   */<a name="line.1292"></a>
<FONT color="green">1293</FONT>    //  public final &lt;P,R extends Serializable&gt; Promise&lt;R&gt;<a name="line.1293"></a>
<FONT color="green">1294</FONT>    //  when(final P reference, final Do&lt;P,R&gt; observer) {<a name="line.1294"></a>
<FONT color="green">1295</FONT>    //      try {<a name="line.1295"></a>
<FONT color="green">1296</FONT>    //          return when(Object.class, ref(reference), observer);<a name="line.1296"></a>
<FONT color="green">1297</FONT>    //      } catch (final Exception e) { throw new Error(e); }<a name="line.1297"></a>
<FONT color="green">1298</FONT>    //  }<a name="line.1298"></a>
<FONT color="green">1299</FONT>    //<a name="line.1299"></a>
<FONT color="green">1300</FONT>    //  /**<a name="line.1300"></a>
<FONT color="green">1301</FONT>    //   * Registers an observer on an {@linkplain #_ eventual reference}.<a name="line.1301"></a>
<FONT color="green">1302</FONT>    //   * &lt;p&gt;<a name="line.1302"></a>
<FONT color="green">1303</FONT>    //   * The implementation behavior is the same as that documented for the<a name="line.1303"></a>
<FONT color="green">1304</FONT>    //   * promise based {@link #when(Promise, Do) when} statement.<a name="line.1304"></a>
<FONT color="green">1305</FONT>    //   * &lt;/p&gt;<a name="line.1305"></a>
<FONT color="green">1306</FONT>    //   * @param &lt;P&gt; {@code observer}'s parameter type<a name="line.1306"></a>
<FONT color="green">1307</FONT>    //   * @param reference observed reference<a name="line.1307"></a>
<FONT color="green">1308</FONT>    //   * @param observer  observer, MUST NOT be {@code null}<a name="line.1308"></a>
<FONT color="green">1309</FONT>    //   */<a name="line.1309"></a>
<FONT color="green">1310</FONT>    //  public final &lt;P&gt; void<a name="line.1310"></a>
<FONT color="green">1311</FONT>    //  when(final P reference, final Do&lt;P,Void&gt; observer) {<a name="line.1311"></a>
<FONT color="green">1312</FONT>    //      try {<a name="line.1312"></a>
<FONT color="green">1313</FONT>    //          when(Void.class, ref(reference), observer);<a name="line.1313"></a>
<FONT color="green">1314</FONT>    //      } catch (final Exception e) { throw new Error(e); }<a name="line.1314"></a>
<FONT color="green">1315</FONT>    //  }<a name="line.1315"></a>
<FONT color="green">1316</FONT>    //<a name="line.1316"></a>
<FONT color="green">1317</FONT>    //  /**<a name="line.1317"></a>
<FONT color="green">1318</FONT>    //   * Causes a compile error for code that attempts to cast a promise to a<a name="line.1318"></a>
<FONT color="green">1319</FONT>    //   * concrete type.<a name="line.1319"></a>
<FONT color="green">1320</FONT>    //   * &lt;p&gt;<a name="line.1320"></a>
<FONT color="green">1321</FONT>    //   * If you encounter a compile error because your code is linking to this<a name="line.1321"></a>
<FONT color="green">1322</FONT>    //   * method, replace the specified concrete type with an<a name="line.1322"></a>
<FONT color="green">1323</FONT>    //   * {@linkplain Proxies#isImplementable allowed} proxy type. For example,<a name="line.1323"></a>
<FONT color="green">1324</FONT>    //   * &lt;/p&gt;<a name="line.1324"></a>
<FONT color="green">1325</FONT>    //   * &lt;kbd&gt;final Observer o_ = _.cast(Observer.class, op);&lt;/kbd&gt;<a name="line.1325"></a>
<FONT color="green">1326</FONT>    //   * &lt;p&gt;becomes:&lt;/p&gt;<a name="line.1326"></a>
<FONT color="green">1327</FONT>    //   * &lt;kbd&gt;final Receiver&amp;lt;?&amp;gt; o_ = _.cast(Receiver.class, op);&lt;/kbd&gt;<a name="line.1327"></a>
<FONT color="green">1328</FONT>    //   * @param &lt;R&gt; referent type to implement<a name="line.1328"></a>
<FONT color="green">1329</FONT>    //   * @param type      ignored<a name="line.1329"></a>
<FONT color="green">1330</FONT>    //   * @param promise   ignored<a name="line.1330"></a>
<FONT color="green">1331</FONT>    //   * @throws AssertionError   always thrown<a name="line.1331"></a>
<FONT color="green">1332</FONT>    //   */<a name="line.1332"></a>
<FONT color="green">1333</FONT>    //  static public &lt;R extends Serializable&gt; void<a name="line.1333"></a>
<FONT color="green">1334</FONT>    //  cast(final Class&lt;R&gt; type,<a name="line.1334"></a>
<FONT color="green">1335</FONT>    //       final Promise&lt;?&gt; promise) { throw new AssertionError();}<a name="line.1335"></a>
<FONT color="green">1336</FONT>    }<a name="line.1336"></a>




























































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